Part 4 — CHAPTER V. (continued 2)

The carcass-rockets are armed with strong iron conical heads, containing a composition as hard and solid as iron itself, and which, when once inflamed, cannot be extinguished. A 32 pounder carcass rocket will penetrate 9 feet in common ground. They have been known to pierce through several floors, and through the sides of houses. For field service, the 24, 18, 12, and 6 pounders are commonly used. The ranges of the eight-inch, seven-inch, and six-inch rockets, are from 2000 to 2500 yards, and the quantity of combustible matter, or bursting powder, from 25 lbs. to 50 lbs. These sized rockets are equally efficient for the destruction of bomb proofs, or the demolition of strong buildings. The largest rocket that has yet been constructed has not exceeded 300 weight. It is proposed, however, to make them from half a ton to a ton in weight.

The 42 and 32 pounders, which are used in bombardment, will convey from 7 lbs. to 10 lbs. of combustible matter each, and have a range of upwards of 3000 yards. The 24 pounder is equal to the propelling of the coehorn shell, or 12 pounder shot. It is, from the saving in weight, generally preferred to the 32 pounder. The eighteen-pounder, which is the first of the light nature of rockets, is armed with a nine pound shot or shell; the twelve-pounder, with a six do.; the nine-pounder, with a grenade; and the six-pounder, with a 3 lb. shot or shell.

The following table presents a general view of the ranges, elevations, and other particulars of several of the most useful descriptions of Congreve rockets.

Nature of ammunition. Armed with Extreme range. Elevation for extreme range.

Carcasses, yards.

42 Pounder carcass rockets. large, 18lbs. of combustible matter; } not less

small, 12 lbs. do.} 3,500than 60°

42 Pounder shell rockets. Shells, 5½, 12 pr. spherical.}

32 Pounder carcass rockets. large, 18 lbs. of combustible matter; 2,00060°

medium 12 lbs. = 13 inch carcass; 2,50060° to 55°

small, 8 lbs. = 10 inch carcass. 3,00055°

32 Pounder shell rockets. shells, 9 pr. spherical. 3,00050°

32 Pounder case shot rockets. Case{large, 200 carbine balls. 2,50055°

shot,{small, 100 do. 3,00050°

32 Pounder explo­sion rockets. Strong iron containing from

from 5 lbs. to 12 lbs. of powder, to burst by fusées. 2500 800055°

12 Pounder case shot rockets. Case{large, 72 carbine balls. 2,00045°

shot,{ small, 48 carbine balls. 2,50045°

From the preceding table, it will be seen, that the 32 pounder carcass rocket will range 3000 yards, with the same quantity of combustible matter as that contained in a ten-inch spherical case, and 2500 yards, with the same quantity as that of the thirteen-inch spherical carcass. The twelve pounder case-shot rocket, which is so portable that it may be used with the facility of musquetry, has a range nearly double that of field artillery, carrying as many bullets as the six pounder spherical case: add to which, that, from the nature of the combination of the rocket, these bullets are projected from it in any part of its track, with an increase of velocity, by which its operation becomes frequently more destructive at that point, where any different species of ammunition ceases to be effective. Of this description of rocket-case-shot, one hundred soldiers will carry into action, in any situation where musquetry can act, 300 rounds, and 10 frames for discharging them; from each of which, four rounds may be fired in a minute. Of the same description of case-shot, four horses will carry 72 rounds, and four frames; from which may be fired 16 rounds in a minute. The rockets used by cavalry are twelve pounders, armed with a 6 pounder shell or case shot; each horse carrying four of these rockets. To detail the arrangement of the rocket corps, the weight of ammunition carried by the troop horse, and other particulars, would require more space than we can conveniently appropriate to these subjects.

We may remark, however, that the heavier species of rockets, as the 32 pounder or 24 pounder, as also the 18 and 12 pounders, are sometimes carried in cars of a peculiar description; which not only convey the ammunition, but are contrived also to discharge each two rockets in a volley, from a double iron-plate trough. This trough is of the same length as the boxes for the sticks, and travels between them; but being moveable, may, when the car is unlimbered, be shifted into its fighting position, at any angle from the ground ranges, or point blank, up to 45°, without being detached from the carriage. The limbers are always in the rear. The rockets are fired with a port-fire and long stick.

When used by infantry, one man in ten, carries a frame of a very simple construction, standing on three legs like a theodolite, when spread. It is mounted at top with an open cradle, from which the rockets are discharged, either for ground ranges, or at any required elevation.

When they are used for bombardment, they are discharged from frames of a different, though simple, construction; and, in many cases, the frames are dispensed with, as they are thrown from a battery, erected for the purpose.

For the defence of a pass, or for covering the retreat of an army, the rockets are laid in batteries of 100 or 500 in a row, according to the extent of the ground to be protected. One man may fire the whole.

With regard to their use in the naval service, some additional remarks may be interesting.

We observed, that, in consequence of there being no reaction in these projectiles on the point of discharge, rockets may be used in the smallest boats of the navy. These rockets carry a quantity of combustible matter, and, according to the ordinary system, would require to be thrown from the largest mortars, and from ships of very heavy tonnage. The 12 and 18 pounder have been fired from a four-oared gig. They may be made to ricochet in the water at low angles. In boarding, they have been recommended, to be thrown into the port holes of the enemy. They have also been recommended for fire-ships, in order to produce an extensive and devastating fire among the ships of the enemy.

Besides the advantages, which rockets possess, and of which we have spoken; namely, that it is a species of projectile, containing within itself the propelling power, by which heavy ordnance is dispensed with, and that an extensive fire may be kept up, by a few men, against any important point; there is another advantage said to be peculiar to them; viz. that they may be employed in a variety of cases, in which the usual artillery, from the nature of the ground, or other impediments, cannot be rendered effective; and that, in several bombardments, in consequence of their trifling reaction, they may be thrown from cutters and small boats, and, therefore, from points, which could never be approached by the vessels, usually employed in that service. With respect to the expense of the formation of war-rockets, calculations have been made, by which it appears, that their cost is less than the usual expense of carcasses.

We are informed on this head, that it is the cheapest of all ammunition, depending on the projectile force of gunpowder. For a 32 pounder carcass rocket costs only 1l. 1s. 11d. complete for service, and its equivalent, the 10 inch spherical carcass, with the charge of powder necessary to convey it 3000 yards, which power is contained in the rocket, costs 1l. 2s. 7d., independent of any charge for the mortar, mortar bed, platform, difference of transport, &c. A vessel of 300 tons will carry 5000 of them at least. But the comparison, as to the expense, is still more in favour of the rocket, when compared with the larger nature of carcasses. The 15 inch spherical carcass costs 1l. 17s. 11¹/₂d. to throw 2500 yards; while its equivalent rocket costs but 1l. 5s. being a saving on the first cost, of 12s. 11¹/₂d.

Notwithstanding all the encomiums, bestowed on the Congreve rockets by the English, the French entertain a different opinion of them. For the following remarks, we are indebted to Ruggeri, (Pyrotechnie Militaire, p. 278), by which it appears, that Congreve was not the original inventor. He acknowledges, however, that they experienced the sad effects of them; and we do not offer this remark with any sort of prejudice, but as an acknowledgment, that the French experienced their "sad effects." Ruggeri says, that the Congreve rocket is nothing more than he described in his Elements of Pyrotechny five years before they were known to the English. It is, therefore, wrong, he adds, that we regard it as an English invention. It was invented, says he, by a naval officer at Bordeaux, and ought not, he further remarks, to be regarded as a useful weapon in war. The reason he gives is, that its utility must depend upon places and circumstances. If it is required, he adds, to attack a fleet, we must employ two or three hundred before making any impression; because we cannot direct a firing rocket, as a cannon or ball. This is certainly a great inconvenience. He makes the cost also much greater than the English calculation; namely, for a single one of them ten times more than for a red-hot shot. Ruggeri, however, is candid enough to say, that, notwithstanding he differs in opinion, he is far from opposing any trials or experiments, made with the view of improving or perfecting it; but is decidedly of opinion, that it can never be employed at sea with the same advantage as bombs and cannon-ball.

Ruggeri published, in the Journal of Paris, in September, 1809, a letter, in reply to a writer, who had published some reflections on incendiary rockets, from which, as it throws some light on this subject, we shall here introduce a few extracts:

"Although Monsieur, the cannonier of Ostend, may not have given the precise construction of the rocket, which we name the sky-rocket, and of which the English have made so criminal a use, I will commence at first by assuring you, that I coincide perfectly with him, in the preference he gives to howitzes, bombs, and other projectiles, which are used by civilized nations. He has very satisfactorily demonstrated their advantages over the Congreve rocket. I will only add, that bombs and howitzes have also the advantage of being one-fifth cheaper, and projected with greater facility.

"The Congreve rocket cannot be of any particular advantage, because it only carries fire to the place where it falls; and if we wish to use them against any vessel whatever, it is impossible to assure ourselves of a direction on a given point, as many difficulties occur in projecting them.

"The merit of the invention of these rockets does not belong to the English.

"This invention was made by a Frenchman, a captain of a privateer, who made the first attempt to use them about seventeen years since, (1795).

"The English have perfected, or rather have modified this rocket.

"It is sometime since I offered a kind of bomb, which may be used with more facility than the common kind. This bomb has the advantage over the Congreve rocket: 1st, Because it is less troublesome to use; 2dly, It may be made of any diameter or size, and consequently suited to all calibers; 3dly, The place and time of its fall is readily determined; and fourth, and lastly, It bursts into pieces, and attaches itself to all combustible bodies, with which it meets.

"It remains for me to say, that it is not the powder which moves the rocket, but a composition almost as strong. The powder, which is used in the Congreve rocket, is intended to destroy the machine after it has produced its destructive effects." See Pyrotechnie Militaire, p. 278.

The difference between incendiary rockets, and common signal rockets, is in the interior. Instead of the furniture, or garnishing pot and head, a conical head of sheet iron is substituted, in which several holes are made to suffer the composition it contains to burn more readily. The composition is the same as that for fire-rockets; but is coarsely pulverized, and mixed with an equal quantity of the composition of fire-lances. These rockets are employed with advantage to burn a city, or vessels in a harbour. The cone, with which they are capped, enables them to penetrate the roofs of houses, and set them on fire.

Sec. XXV. Sky-Rockets (Meurtrières.)

The sanguinary or murdering rocket is made in the same manner as the preceding. They have neither head nor pot; but, in their place, they are furnished with a cone of beaten or solid iron. This cone is the appendage, or weapon, which produces such destructive effects. These rockets, when they fall upon the troops of an enemy, wound them very dangerously, without their being able to prevent it. The advantage, more particularly derived, is, that they may be projected from under cover, and to double the distance of ordinary musketry. To make use of these rockets, a box is constructed, whose interior is so arranged as to receive the rockets in regular order. They should be placed in it with their sticks; and, therefore, the case must be made sufficiently large to admit them. By this contrivance, the rockets are sheltered from the fire and water. To discharge them, the box is first inclined on the side next to the heads of the rockets, and in the direction of the place, to which they are to be thrown. A communication is made by leaders, in the manner already mentioned in the preceding part of this work; so that, when the match is fired, or a single rocket, they all are discharged at the same time. The mode of firing rockets either singly or in numbers, the manner of preparing the cases, the different compositions, and the operation of filling, and of furnishing them, &c. are given in the preceding part.

Sec. XXVI. Of the Rocket Light-Ball.

Congreve also invented a species of light-ball, which, when thrown into the air by means of one of his rockets, and having reached the elevation of the rockets' ascent, is detached from it with an explosion, and remains suspended in the air by a small parachute, to which it is connected by a chain. Thus, in lieu of the transient momentary gleam, obtained by the common light ball, a permanent and brilliant light is obtained, and suspended in the air for five minutes at least, so as to afford time and light sufficient to observe the motions of an enemy, either on shore or at sea; where it is particularly useful in chasing, and for giving distant and more extensive night signals. It is to be observed, that nothing of this kind can be obtained by the projectile force of either guns or mortars; because the explosion infallibly destroys any construction, that could be made to produce the suspension in the air.

We have seen no account of any experiments, which have been made with it.

Sec. XXVII. Of the Floating Rocket Carcass.

Congreve also applied his rocket, and the parachute, for the purpose of conveying combustible matter to distances far beyond the range of any known projectile force, at the same time that it is cheap, simple, and portable. The floating carcass, like the light-ball, is thrown into the air, attached to a rocket, from which being liberated at its greatest altitude, and suspended to a small parachute, it is driven forward by the wind, and will, in a moderate breeze, afford ranges at least double those of the common carcass. It may, therefore, for naval purposes, be thrown from a blockading squadron, in great quantities, by a fair wind, against any fleet or arsenal, without the smallest risk, or without approaching within range of either guns or mortars. The rocket containing the carcass is no larger than the 32 pounder carcass rocket; and the whole expense, added to the rocket, does not exceed five shillings. Nor are the approaches of the carcass itself necessarily visible by night; as it may be so arranged, as not to inflame, till some time after it has settled. It is evidently, therefore, capable of becoming a harassing weapon, if the account of it be true; and, among large fleets and flotillas, it may do as much injury as any other carcass, by lodging unperceived in the rigging, or lighting on extensive arsenals, in such situations, where other means of annoyance could not be used.

Sec. XXVIII. Observations on Rockets.

The following remarks on the subject of rockets by M. Bigot, (Traité d'Artifice de Guerre, p. 131,) may be interesting to the reader.

Authors, who have written on rockets, are of opinion, that the height of the different kinds of rockets should not be increased on account of their diameter; because, as the diameter increases, the rocket also increases in weight and surface; and if augmented in height in the same ratio, its power of ascension would be feeble. It is from this reasoning, together with practice, that they have determined the height of empty cases. Some have given the proportion of six times their exterior diameter, and others again have made them a third longer than the piercer. There has resulted from this difference of opinion, such an irregularity in the formation of rockets, that artificers or fire-workers were left in uncertainty as to the best mode to be pursued. To avoid, however, this embarrassment, if we consider the diameter of the base of the piercer of any kind of rocket as one-third of the exterior diameter of the case, the small end must be the one-sixth part of it; and the piercer and the cone are of the same diameter, and the surface of the one is equal to the surface of the other. We might conclude, accordingly, that the increase of the height of the case, should be the same with all kinds of rockets. It appears by different authors, that the ancient and modern fire-workers have fixed the dimensions of rockets and their piercers, by various experiments. If we take for granted all the heights of the piercers, or the rockets themselves, we obtain a curve of double or treble reflection, which is very evidently in opposition to the above principles, and of the law which results from them.

Experiments prove, that to make a good rocket of half an inch in diameter, the piercer must be five times and a third of the same diameter; and for a rocket of three inches, the piercer, or broach, as it is sometimes called, is only four times the diameter in height. To determine, however, the height of the piercer in general, greater than the preceding, it is found necessary to have some satisfactory result, in order to employ, mathematically speaking, less times of the exterior diameter of the rocket. The half-inch and three-inch rocket are the extremes of an increasing arithmetical progression; and their equivalents, 5¹/₃ and 4 diameters is the extreme of a similar, but decreasing progress; but if we insert the same number of arithmetical mean between the two extremes of each of these two progressions, and then continue them indifferently, the terms of the first will express the diameter of as many different cases; and those of the second, the height of the corresponding piercers. They will be, for instance, in the two following proportions:

÷ 678 9101112 1314,&c. 36.

÷ 5¹⁴/₄₅5¹²/₄₅5¹¹/₄₅ 5⁹/₄₅5⁷/₄₅5⁷/₄₅5²/₄₅ 5¹/₄₅4⁴⁴/₄₅&c.4.

The first of which has unity for its common difference. It has been found, that, by inserting in each, a mean of 29, the height of the piercers will correspond with the superior diameter, which is less, or regulated by their respective diameters. Besides, as the diameters go on augmenting, the rockets are proportionably increased in height, but only in an inverse order, until the 58th term included, and beyond which they decrease, until they become negative, which appears to indicate that the term appertains to the diameter of the rocket, and without any uncertainty.

It results from the intimate relation of these two progressions, that, in stopping at the 58th term, if we bring back on an axis as it were, the height of the piercers, we obtain a straight instead of a curved line.

Bigot has given two tables relative to the construction of rockets, and, as their use is seen by mere inspection, we here introduce them without remark.

They comprehend the dimensions of rockets of different calibers, compared with the exterior and respective diameter of each kind; and relative to the dimensions of the tools of sky-rockets of different calibers, and also compared with the exterior and respective diameter of each.

It will be seen, on an examination of these tables, that all the data are satisfactorily given; so that, in the construction of rockets, the artificer will find them extremely useful, if not absolutely necessary.

The principles on which these tables are founded, may be depended on, inasmuch as M. Bigot has taken considerable pains on that head; and, consequently, the calculations, which follow, and the proportions, established for the construction of rockets in general, are sufficiently conclusive.

Diameter of the rocket. Height of tools of wood.Diameter of the tools of wood. Dimension of mallets.

Rammers, &c. Rammers.

Name of the Rocket. For charging the head not comprised.

Exterior.Interior.Roller. 123Solid 4 Pot.Conical head.To run. To charge.Of pots.Sockets of the pot. Base of conical head.Ladle.Diam­eter. Length.

inch.Diam.D. D.D.D.D. D.D.D.D. D.D.D.D. inches.inches.

Small Partement,½⅔24 6⅓4⁵/₉2⁷/₉1⅓ 31⅔⅔⁷/₁₂ 1⅔⅔1⅔⅔ 2¾3⅓

Partement,¾idem.16 6²/₉4¹³/₂₇2⁶/₂₇idem. 2⅔1⁵/₉idem.¹¹/₁₈ 1⁵/₉⁷/₉1⁵/₉idem. 2¾3⅓

Marquise,1idem.12 6¹/₁₂4⁷/₁₈2²⁵/₃₆idem. 2⅓1½idem.idem. 1½⁵/₆1½idem. 3½4¼

Double marquises1¼idem.idem. 5¹⁴/₁₅4¹³/₄₅2²⁹/₄₅idem. 2¹/₅1⁸/₁₅idem.³/₅ 1⁸/₁₅¹³/₁₅1⁸/₁₅idem. 3½4¼

Ditto, for 4 doz.1½idem.10 5⁷/₉4⁵/₂₇2¹⁶/₂₇idem. 21½idem.¹¹/₁₈ 1½⁵/₆1½idem. 45

Rocket of2idem.9 5⅜3³¹/₃₆2²⁵/₇₂1¹/₆ 1¾idem.idem.⅝ idem.⅞idem.idem.}

Ditto,2½idem.8²/₅ 5¹/₁₅3²⁹/₄₅2²/₉1²/₁₅ 1½idem.idem.¹⁹/₃₀ idem.⁹/₁₀idem.idem.}

Ditto,3idem.8 4⁷/₉3⁴/₉2¹/₉1¹/₉ 1⅓idem.idem.²³/₃₆ idem.¹¹/₁₂idem.idem.} 5½6⅔

Ditto,4idem.6⁵/₆ 4¼3³/₃₂1¹⁵/₁₆1¹/₈ 1¹/₁₆idem.idem.³¹/₄₈ idem.¹⁵/₁₆idem.idem.}

Ditto,5idem.6 3⁴³/₆₀2¹³³/₁₈₀1¹³⁷/₁₈₀1⁷/₆₀ ⁹/₁₀idem.idem.¹³/₂₀ idem.¹⁴/₁₅idem.idem.}

Diameter of rockets. HEIGHT OF Diameter of the parts of the piercer.

Name of the Rockets.Charged rockets, Button Total of the piercer, button Exterior Button Screw at

Exterior.Interior.Empty cases. button,&c. included.Massive Rockets.Piercers. & their cylinder.Culots.and culot, comprised. Screw.Base.of small end.and cylinder. Culot.the base.

inch.Diam. D.D.D.D. D.D.D.D. D.D.D.D. D.

Small partement,½⅔ 7⅓6⁵/₆⅔5¹/₃ ⅔1⅔7⅔¼ ⅓¹/₆⅔1 1

Partement,¾idem. idem.6⁷/₉idem.5²/₉ idem.idem.7⁵/₉2⅔ idem.idem.idem.idem. ⁷/₉

Marquise,1idem. 7⁷/₁₂6⁷/₁₂idem.5¹/₁₂ idem.idem.7¹/₁₂2½ idem.idem.idem.idem. ⅔

Double marquise of 3 doz1¼idem. 76⁷/₁₅idem.4¹⁴/₁₅ idem.1¹/₅6⁴/₅2 idem.idem.idem.idem. ³/₅

Ditto, 4 doz.1½idem. 6⁷/₉6⁵/₁₈idem.4⁷/₉ idem.1¹/₁₈6½1⁵/₆ idem.idem.idem.idem. ⁵/₉

Rocket of2idem. 6⅜5⅞½4¹³/₂₄ idem.⅞6¹/₁₂1½ idem.idem.idem.idem. ½

Ditto,2½idem. 6¹/₁₅5¹⁷/₃₀⁷/₁₅4⁴/₁₅ idem.⁴/₅5¹¹/₁₅1³/₁₀ idem.idem.idem.idem. idem.

Ditto,3idem. 5⁷/₉5⁵/₁₈⁴/₉4 idem.⅔5⅓1¹/₆ idem.idem.idem.idem. idem.

Ditto,4idem. 5¼4⁷³/₇₆¹¹/₂₄3¹⁵/₃₂ idem.½4⁶¹/₉₆¹⁵/₁₆ idem.idem.idem.idem. ⁵/₁₂

Ditto,5idem. 4⁴³/₆₀4¹³/₆₀⁹/₂₀2¹⁴/₁₅ idem.²/₅4⁴/₅ idem.idem.idem.idem. ²/₅

Note. The rockets of two inches, and those between that and three inches, require to be beaten with four rammers, independently of that which is solid; and also those above three inches, require five. The rolling board should be sufficiently large for the cases we wish to form; viz. one of twenty-eight inches in length, and six inches in breadth for small rockets; one of thirty inches in length, and ten inches in breadth for middlesized rockets; and one of thirty-six inches by eighteen for the largest rockets.

(TABLE I: Part 1 of 3)

Diameter of the rocket. Height of tools of wood.

Rammers, &c.

Name of the Rocket. For charging the head not comprised.

Exterior.Interior. Roller.123Solid 4

inch.Diam. D.D.D.D.D.

Small Partement,½⅔ 246⅓4⁵/₉2⁷/₉1⅓

Partement,¾idem. 166²/₉4¹³/₂₇2⁶/₂₇idem.

Marquise,1idem. 126¹/₁₂4⁷/₁₈2²⁵/₃₆idem.

Double marquises1¼idem. idem.5¹⁴/₁₅4¹³/₄₅2²⁹/₄₅idem.

Ditto, for 4 doz.1½idem. 105⁷/₉4⁵/₂₇2¹⁶/₂₇idem.

Rocket of2idem. 95⅜3³¹/₃₆2²⁵/₇₂1¹/₆

Ditto,2½idem. 8²/₅5¹/₁₅3²⁹/₄₅2²/₉1²/₁₅

Ditto,3idem. 84⁷/₉3⁴/₉2¹/₉1¹/₉

Ditto,4idem. 6⁵/₆4¼3³/₃₂1¹⁵/₁₆1⅛

Ditto,5idem. 63⁴³/₆₀2¹³³/₁₈₀1¹³⁷/₁₈₀1⁷/₆₀

(TABLE I: Part 2 of 3)

Diameter of the rocket. Height of tools of wood.Diameter of the tools of wood.

Rammers.

Name of the Rocket.

Sockets

Exterior.Interior. Pot.Conical head.To run.To charge.Of pots.of the pot.

inch.Diam. D.D.D.D.D.D.

Small Partement,½⅔ 31⅔⅔⁷/₁₂1⅔⅔

Partement,¾idem. 2⅔1⁵/₉idem.¹¹/₁₈1⁵/₉⁷/₉

Marquise,1idem. 2⅓1½idem.idem.1½⁵/₆

Double marquises1¼idem. 2¹/₅1⁸/₁₅idem.³/₅1⁸/₁₅¹³/₁₅

Ditto, for 4 doz.1½idem. 21½idem.¹¹/₁₈1½⁵/₆

Rocket of2idem. 1¾idem.idem.⅝idem.⅞

Ditto,2½idem. 1½idem.idem.¹⁹/₃₀idem.⁹/₁₀

Ditto,3idem. 1⅓idem.idem.²³/₃₆idem.¹¹/₁₂

Ditto,4idem. 1¹/₁₆idem.idem.³¹/₄₈idem.¹⁵/₁₆

Ditto,5idem. ⁹/₁₀idem.idem.¹³/₂₀idem.¹⁴/₁₅

(TABLE I: Part 3 of 3)

Diameter of the rocket. Diameter of the tools of wood.Dimension of mallets.

Name of the Rocket. Base of conical

Exterior.Interior. head.Ladle.Diameter.Length.

inch.Diam. D.D.inches.inches.

Small Partement,½⅔ 1⅔⅔2¾3⅓

Partement,¾idem. 1⁵/₉idem.2¾3⅓

Marquise,1idem. 1½idem.3½4¼

Double marquises1¼idem. 1⁸/₁₅idem.3½4¼

Ditto, for 4 doz.1½idem. 1½idem.45

Rocket of2idem. idem.idem.}

Ditto,2½idem. idem.idem.}

Ditto,3idem. idem.idem.}5½6⅔

Ditto,4idem. idem.idem.}

Ditto,5idem. idem.idem.}

(TABLE II: Part 1 of 3)

Diameter of rockets. HEIGHT OF

Name of the Rockets. Charged

rockets,

Exterior.Interior. Empty cases.button, &c.incl.Massive Rockets.Piercers.

inch.Diam. D.D.D.D.

Small partement,½⅔ 7⅓6⁵/₆⅔5⅓

Partement,¾idem. idem.6⁷/₉idem.5²/₉

Marquise,1idem. 7⁷/₁₂6⁷/₁₂idem.5¹/₁₂

Double marquise of 3 doz.1¼idem. 76⁷/₁₅idem.4¹⁴/₁₅

Ditto, 4 doz.1½idem. 6⁷/₉6⁵/₁₈idem.4⁷/₉

Rocket of2idem. 6⅜5⅞½4¹³/₂₄

Ditto,2½idem. 6¹/₁₅5¹⁷/₃₀⁷/₁₅4⁴/₁₅

Ditto,3idem. 5⁷/₉5⁵/₁₈⁴/₉4

Ditto,4idem. 5¼4⁷³/₇₆¹¹/₂₄3¹⁵/₃₂

Ditto,5idem. 4⁴³/₆₀4¹³/₆₀⁹/₂₀2¹⁴/₁₅

(TABLE II: Part 2 of 3)

Diameter of rockets. HEIGHT OF

Name of the Rockets. Total of

Buttonthe piercer

Exterior.Interior. & their cylinder. Culots. and culot comprised. Screw.

inch.Diam. D.D.D.D.

Small partement,½⅔ ⅔1⅔7⅔¼

Partement,¾idem. idem.idem.7⁵/₉2⅔

Marquise,1idem. idem.idem.7¹/₁₂2½

Double marquise of 3 doz.1¼idem. idem.1¹/₅6⁴/₅2

Ditto, 4 doz.1½idem. idem.1¹/₁₈6½1⁵/₆

Rocket of2idem. idem.⅞6¹/₁₂1½

Ditto,2½idem. idem.⁴/₅5¹¹/₁₅1³/₁₀

Ditto,3idem. idem.⅔5⅓1¹/₆

Ditto,4idem. idem.½4⁶¹/₉₆¹⁵/₁₆

Ditto,5idem. idem.²/₅4⁴/₅

(TABLE II: Part 3 of 3)

Diameter of rockets. Diameter of the parts of the piercer.

Name of the Rockets. ExteriorButtonScrew

Exterior.Interior. Base. of small end.and cylinder. Culot. at the base.

inch.Diam. D.D.D.D.D.

Small partement,½⅔ ⅓¹/₆⅔11

Partement,¾idem. idem.idem.idem.idem.⁷/₉

Marquise,1idem. idem.idem.idem.idem.⅔

Double marquise of 3 doz.1¼idem. idem.idem.idem.idem.³/₅

Ditto, 4 doz.1½idem. idem.idem.idem.idem.⁵/₉

Rocket of2idem. idem.idem.idem.idem.½

Ditto,2½idem. idem.idem.idem.idem.idem.

Ditto,3idem. idem.idem.idem.idem.idem.

Ditto,4idem. idem.idem.idem.idem.⁵/₁₂

Ditto,5idem. idem.idem.idem.idem.²/₅

Note. The rockets of two inches, and those between that and three inches, require to be beaten with four rammers, independently of that which is solid; and also those above three inches, require five. The rolling board should be sufficiently large for the cases we wish to form; viz. one of twenty-eight inches in length, and six inches in breadth for small rockets; one of thirty inches in length, and ten inches in breadth for middlesized rockets; and one of thirty-six inches by eighteen for the largest rockets.

Sec. XXIX. Of the Succouring Rocket.

The succouring, or marine rocket, is a name given to a rocket, which is sufficiently large to convey a small cord or rope to some distance from a vessel, and by its means to save the lives of persons in danger of shipwreck. Rockets for this purpose should be at least two inches in interior diameter. The rod should be of the same length and thickness as a rocket of half this caliber. To this rod is tied the cord, which must be light, and yet strong, and when the rocket is fired, the string should be arranged loose, so that no impediment is experienced in the flight of the rocket.

The applications of the succouring rocket are two in particular: viz. In case a seaman should fall overboard, and in case of shipwreck; in the former, to throw a cord to some distance, and in the latter, to convey a cord from the ship to the shore, should a vessel be stranded on a beach. Several methods have been proposed for the same purpose, namely, that of conveying a line or rope to shore, when the surf is too high for a small boat to live in it.

The invention of lieut. Bell, described in the Annales des Arts et Manufactures, and in the Archives des Découvertes, ii, 120, is designed for a similar purpose as the succouring rocket. Mr. Bell's invention consists simply in throwing a rope from a vessel by means of a mortar, attaching it to a shell, in order to make a communication from a vessel in danger to the shore. For this contrivance, he received one hundred guineas.

Several experiments were made with it, which were satisfactory.

In the essays, published by Mr. Fulton, a contrivance of this kind is suggested, using, however, an instrument similar to a harpoon, to which a rope is attached. This harpoon is thrown by a long gun. It is calculated, also, as the harpoon for this purpose is furnished with several barbs, to pierce and secure an enemy's vessel.

Sec. XXX. Of the Greek Fire.

It is not known precisely what the composition of the Greek fire was. It was invented by Callinicus of Hellipolis, a town in Syria, who used it with so much skill and effect during a naval engagement, that he destroyed a whole fleet belonging to the enemy, in which were embarked thirty thousand men. It is defined to be a sort of artificial fire, which insinuates itself beyond the surface of the sea, and which burns with increased violence, when it mixes with water. Its directions are contrary to the course of natural fire; for the flames, we are told, will spread themselves downwards, to the right or left, agreeably to the moment that is given.

It was used in the year 1679, and was known and used in 1291. It was certainly liquid, and employed in many different ways; but, chiefly, on board ships, being thrown from large engines on the ships of the enemy. This fire was sometimes kindled in particular vessels, which might be called fire-ships, and which were introduced among a hostile fleet. Sometimes it was put into jars and other vessels, which were thrown at the enemy by means of projectile machines; and sometimes it was squirted by soldiers from hand-engines, or, as it appears, blown through pipes. This fire was discharged from the fore part of ships, by a machine constructed of copper and iron, the extremity of which resembled the open mouth and jaws of a lion or other animal. They were painted, and even gilded, and, it appears, were capable of projecting the fire to a great distance.

Professor Beckman, who examined all the ancient authors respecting the Greek fire, expressly says, that the machines which the ancients employed to throw this fire were spouting engines. He also observes (History of Invent. iv, p. 85) that "John Cameniata, speaking of his native city, Thessalonica, which was taken by the Saracens in the year 901, says, that the enemy threw fire into the wooden works of the besieged, which was blown into them by means of tubes, and thrown from other vessels. This passage, which I do not find quoted in any of the works that treat on the Greek fire, proves, that the Greeks, in the beginning of the tenth century, were no longer the only people acquainted with the art of preparing this fire, the precurser of our gunpowder. The Emperor Leo, who about the same period wrote his art of war, recommends such engines, with a metal covering, to be constructed in the fore part of ships; and he twice afterwards mentions engines for throwing out Greek fire. In the east, one may easily have conceived the idea of loading some kind of pump with the Greek fire; as the use of a forcing pump for extinguishing fires was long known there before the invention of Callinicus."

Writers differ considerably as to the composition of Greek fire, properly so called, as there were many preparations, some hundred years after the discovery, which went under the name of Greek fire. Certain it is, that the Greeks had a knowledge of a very highly combustible preparation, which water would not extinguish, and which, from its nature, must have had the property of decomposing water itself, or possessed so much oxygen, as to support the combustion of the inflammable substances, even in contact with water.

Mr. Parke, (Chem. Catechism, p. 465), speaking of some of the uses of nitre or saltpetre, says, that "for the same purposes it was used by the ancients in that destructive composition of antiquity, the Greek fire. Sulphur, rosin, camphor, and other combustibles, were melted with it, and in this melted mass, woollen cords were dipped, which were afterwards rolled up for use. These balls being set on fire were thrown into the tents, &c. of the enemy, and as the combustibles were furnished with a constant supply of oxygen from the nitre, nothing could extinguish them." He also observes: "For many centuries, the method of making this dreadful article of destruction was lost; but it has just been discovered by the librarian of the elector of Bavaria, who has found a very old latin manuscript, which contains directions for preparing it."

It appears, however, that it could only be extinguished by urine, sand, &c. James (Mil. Dic. p. 329) says, "it is composed, or made up of naphtha, sulphur, bitumen, gum, and pitch, and it can only be extinguished by vinegar, mixed with urine and sand, or with undressed leather and green hides."

The author of a French work, Œuvres Militaires, says, that a powerful composition, which is not extinguishable with water, may be made of the following substances: viz. pitch, rosin, tallow, camphor, turpentine, saltpetre, liquid varnish, oil of sulphur, linseed, rock oil, flax, and charcoal finely pulverized. The whole is melted together and boiled, and before it grows cold, quicklime in powder is added. It is said to be susceptible of the most subtile and destructive fire.

Bertrandon de la Brocquiere, who was in Palestine in 1432, as counsellor to the Duke of Burgundy, observes, that the Moors were then in possession of the Greek fire. He was present at Barrat, during one of the Moorish celebrations. "It began," says he, "in the evening at sun set. Numerous companies, scattered here and there, were singing and uttering loud cries. While this was passing, the cannon of the castle were fired, and the people of the town launched into the air, 'bien hault et bien loing, une maniére de feu plus gros fallot que je veisse oncques allume.' They told me, they made use of such at sea, to set fire to the sails of an enemy's vessel. It seems to me, that as it is a thing easy to be made, and at a little expense, it may be equally well employed to burn a camp or a thatched village, or in an engagement with cavalry, to frighten their horses.

"Curious to know its composition, I sent the servant of my host to the person who made this fire, and requested him to teach me this method. He returned for answer, that he dared not, for that he should run great danger, were it known; but as there is nothing a Moor will not do for money, I offered him a ducat, which quieted his fears, and he taught me all he knew, and even gave me the moulds in wood, with the other ingredients, which I have brought to France."

Although La Brocquiere may have brought the secret to Europe, yet it does not appear to have been used.

We may justly conclude, that the present gunpowder possesses superior advantages to the Greek fire, and some authors, as Ruggeri, are of opinion, that the account we have of it, that of its fire descending, and the like, are exaggerated.

Porta, (Magie Naturelle), in treating of this subject, observes, that the Greek fire was composed of the charcoal of willow, salt, burnt brandy, sulphur, pitch, frankincense, flax, and camphor, and that camphor alone has the effect of burning in water. He remarks also, that, when Constantinople was attacked, the emperor Leon burnt the vessels, or boats, to the number of 1800, by means of the Greek fire. The Journal des Savants, 1676, p. 148, speaks of the origin and use of the same fire.

In 1249, at the siege of Damietta, the French experienced the fatal effects of it. The Journal des Savants for 1666, mentions a machine, which, when applied against a vessel, communicates fire to it immediately, without injuring the person who uses it. In the French papers for 1797, M. Chevalier announced, that he had invented an inextinguishable incendiary fuse, which is thrown by fire arms, and calculated to set fire to the rigging of ships. In 1759, Dr. Dupré published in the French Journals, that he had invented a composition, which had the same properties and effects as the ancient Greek fire, and that he possessed the means of extinguishing it. An experiment was made at Versailles to the satisfaction of all, and the secret was purchased by Louis XV. The Rev. J. P. Coste, in 1794, laid before the French national convention, a new invention, for the purpose of war, consisting of a carcass composition, which nothing could extinguish, and which resembled in that respect the Greek fire.

Thevenot (Travels in the Levant), says, that in the 52d year of the Hegira, (Anno Domini 672), Constantinople was besieged in the reign of Constantine Prognates, by Yesid, the son of Moavia, the first caliph of the family of the Ammiades; when the Greek emperor found himself so pressed, that he was almost reduced to despair. But the famous engineer, Callinicus, invented a kind of wild fire, which would burn under water, and by this means destroyed the whole fleet.

Gibbon (History of the Decline and Fall of the Roman Empire, vol. vii, p. 282), speaks also of the Greek fire, and observes, that the deliverance of Constantinople may be chiefly ascribed to it. It appears, that Callinicus, the inventor, deserted from the service of the Caliph to that of the Emperor; and Gibbon is of opinion, that this discovery or improvement of the military art, was fortunately reserved for the distressful period, when the degenerate Romans of the east were incapable of contending with the warlike enthusiasm and youthful vigour of the Saracens. He is of opinion, that little or no credit can be given to the Byzantine accounts, as to the composition of this fire; although, from their obscure and fallacious hints, it should seem that the principal ingredient was naphtha, a liquid bitumen which springs from the earth.[39] This was mixed with sulphur, and with the pitch, extracted from the evergreen firs, according to the testimony of Anna Commena, (Alexid, l. xiii, p. 383), and Leo, in the xixth chapter of his Tactics, speaks of the new invention.

Gibbon describes its effects much as we have stated, viz. that the fire was strong and obstinate, and was quickened by water; that sand, urine, and vinegar were the only agents that could damp its fury; that it was used for the annoyance of the enemy, both by sea and land, in battles or in sieges, and was either poured from the rampart in large boilers, or lanched into red-hot balls of stone and iron, or darted in arrows and javelins, twisted round with flax and tow, which had deeply imbibed the inflammable oil; that, at other times, it was deposited in fire ships, or blown through long tubes of copper, fixed on a prow of a galley; that its composition was kept secret at Constantinople, pretending that the knowledge of it came from an angel to the first and greatest of the Constantines, with a sacred injunction not to divulge it under any pretext, &c. He also observes, that, after it was kept secret above four hundred years, and to the end of the 11th century, the method of preparing it was stolen by the Mahometans, who employed it against the crusaders. A knight, it appears, who despised the swords and lances of the Saracens, relates, with heartfelt sincerity, his own fears, at the sight and sound of the mischievous engine, that discharged a torrent of the Greek fire, the feu Gregeois, as it is styled by the more early of the French writers. "It came flying through the air," says Gibbon, quoting Joinville, (Histoire de St. Louis) "like a winged long tailed dragon, about the thickness of a hogshead, with a report of thunder and the velocity of lightning; and the darkness of the night was dispelled by this deadly illumination. The use of the Greek, or as it might now be called, Saracen fire, was continued to the middle of the 14th century, when the scientific or casual compound of nitre, sulphur, and charcoal, effected a new revolution in the art of war, and the history of mankind."

Ramsay, our learned historian, (Universal History, vol. ii, p. 150), gives the same account of the Greek fire. Morse, in his Universal Geography, page 588, observes, that naphtha forms springs in Persia, and, when scattered on the sea, it burns, and the flame is often wafted to a great distance.

For remarks respecting the naphtha of Persia, and the universal fire of the followers of Zoroaster, see the article on Naphtha. In naphtha districts, the quantity of inflammable air is so great, that it is used for fuel.

Since writing the above, we have examined Ruggeri, (Pyrotechnie Militaire, p. 289), and find nothing new. He states the composition of Greek fire, on the authority of others, to consist of naphtha, sulphur, bitumen, camphor, and petroleum; that it was invented by Callinicus, and employed against the Saracens as an incendiary; that Pliny, in his time, mentioned a combustible substance, which was thrown upon armed men, and burnt and destroyed them in the midst of the battle; that it was employed successfully by the successors of Constantine, and its composition was kept a state secret; that the Turks used it, or a composition of a similar nature, at the siege of Damieta, in 1249, forty-five years after the death of Roger Bacon; and, finally, that, when the composition and effects of gunpowder became known, the Greek fire, although it laid the foundation of the invention of gunpowder, was no longer in use, and the secret of the original preparation became lost. See Gunpowder.

Sec. XXXI. Of Mines and Mining.

A mine is a subterraneous passage, dug under the wall or rampart of a fortification, for the purpose of blowing it up by gunpowder; and mining is the art of accomplishing this effect.

The art of mining, having become one of the most essential parts of the attack and defence of places, should be well understood; and requires a perfect knowledge of heights, depths, breadths, and thicknesses; to judge perfectly of slopes and perpendiculars, whether they be such as are parallel to the horizon, or such as are visual; together with the true levels of all kinds of earth. To this may be added, a knowledge of rocks, clays, soil, &c. and the effect of gunpowder.

Mines were made long before the invention of gunpowder. The ancients made galleries, or underground passages, much in the same manner as the moderns, from without, under the walls of places, which they cut off from the foundation, and supported with strong props. The intervals were filled with all manner of combustibles, which, being set on fire, burnt their props, and the wall, being no longer supported, fell, by which a breach was made.

The besieged also made underground passages, from the town, under the besiegers' machines, by which they battered the walls, to destroy them, proving that necessity has been the inventress of mines.

The first mines we read of, since the invention of gunpowder, were made in 1487, by the Genoese, at the attack of Serezanella, a town in Florence. These, however, failed, and they were neglected, till Peter Navarro, being then engineer to the Genoese, and afterwards to the Spaniards, in 1503, against the French, at the siege of the castle del Ovo, at Naples, made a mine under the wall, and blew it up; in consequence of which the castle was taken by storm. Valliers says, that the engineer was Francis George, an Italian.

The place where the powder is lodged, is called the chamber of the mine, or fourneau, and the passage leading to the powder, is called the gallery. The line of the least resistance, is the line drawn from the centre of the chamber, perpendicular to the surface of the ground; and the excavation, called the crater, is the pit or hole, made by springing the mine.

Counter-mines are those made by the besieged, whereas mines are generally made by the besiegers. Both mines and counter-mines, are made in the same manner, and for like purposes, viz. to blow up their enemies and their works.

Galleries, made within the fortification, before the place is attacked, and from which several branches are carried to different places, are generally 4 and 4¹/₂ feet wide, and 5 or 5¹/₂ feet high. The earth is supported from falling in, by arches and walls, as they are to remain for a considerable time. But when mines are made to be used in a short time, then the galleries are but 3 or 3¹/₂ feet wide, and 5 feet high, and the earth is supported by wooden frames, or props.

The gallery being carried on to the place, where the powder is to be lodged, the miners make the chambers. This is generally of a cubical form, large enough to hold the wooden box, which contains the powder necessary for the charge. The box is lined with straw and sand bags, to prevent the powder from contracting dampness.

The chamber is sunk rather lower than the gallery, if the soil permits; but where water is to be apprehended, it must be made higher than the gallery; otherwise the besieged will let in the water, and spoil the mine.

The fire is communicated to the mine by a pipe, or hose, made of coarse cloth, whose diameter is about 1¹/₂ inches, called a saucisson, (for the filling of which, near half a pound of powder is allowed to every foot), extending from the chamber to the entrance of the gallery, to the end of which is fixed a match, that the miner who sets fire to it, may have time to retire before it reaches the chamber.

To prevent the powder from contracting any dampness, the saucisson is laid in a small trough, called an auget, made of boards 3¹/₂ inches broad, joined together lengthwise, with straw in it, and round the saucisson, with a wooden cover nailed upon it.

The quantity of powder, required to charge mines, depends upon the nature of the soil. That which is more tenacious, will require the greatest force to separate its parts. The density may be learned, comparatively speaking, by determining the specific gravity of each kind of soil. The requisites in mining may be ascertained by four simple problems, which relate to the nature of the soil, the diameter of the excavation, the line of least resistance, and the charge.

Table of the quantity of Gunpowder, to raise a cubic fathom of different kinds of Soil.

DENSITY.TENACITY.

NATURE OF THE SOIL.Weight of 1 cubic foot.Quantity of powder to raise 1 cubic fathom.

1. Loose earth or sand. 95 lbs. 8 lbs.

2. Common light soil.12410

3. Loam or strong soil.12712¼

4. Potters' clay, or stiff soil.13513½

5. Clay, mixed with stones.16016

6. Masonry.20521½

The gallery and chamber being ready to be loaded, a strong box of wood is made of the size and figure of the chamber, being about one-third or one-fourth larger than is required for containing the necessary quantity of powder. Against the sides and bottom of the box is put some straw, and this straw is covered over with empty sand bags, to prevent the powder from contracting any dampness. A hole is made in the side, next the gallery, near the bottom, for the saucisson to pass through, which is fixed to the middle of the bottom, by means of a wooden peg, to prevent its loosening from the powder, or to hinder the enemy (if he should reach the entrance) from being able to tear it out. This done, the powder is brought in sand bags, and thrown loosely in the box, and covered also with straw and sand bags. Upon this is put the cover of the box, pressed down very tight with strong props; and, to render them more secure, planks are also put above them, against the earth, and wedged in as fast as possible.

This done, the vacant spaces between the props are filled up with stones and dung, and rammed in the strongest manner. The least neglect in this work will considerably alter the effect of the mine. Then the auget, or small trough, is laid from the chamber to the entrance of the gallery, with some straw at the bottom; and the saucisson laid in it, with straw over it. Lastly, it must be shut with a wooden cover, nailed upon it. Great care must be taken in stopping up the gallery, not to press too hard upon the auget, for fear of spoiling the saucisson, which may hinder the powder from taking fire, and prevent the mine from springing. The gallery is stopped up with stones, earth and dung, well rammed, six or seven feet further from the chamber than the length of the line of the least resistance.[40]

Before closing this article, short as it is, compared with a full view of the subject, which belongs exclusively to engineering, we shall notice, from Belidor, the globe of compression in mines. If we imagine a large globe of earth, homogeneous in all its parts, and a certain quantity of powder lodged in its centre, so as to produce a proper effect without bursting the globe; by setting fire to the powder, it is evident that the explosion will act all round, to overcome the obstacles which oppose its motion; and as the particles of the earth are porous, they will compress each other in proportion as the flame increases, and the capacity of the chamber increases likewise: but the particles of the earth next to the chamber will communicate a part of their motion to those next to them, and those to their neighbours; and this communication will thus continue in a decreasing proportion, till the whole force of explosion is entirely spent; and the particles of earth beyond this term will remain in the same state as they were at first. The particles of earth, that have been acted upon by the force of explosion, will compose a globe, which Mr. Belidor calls the globe of compression. He observed, that, when a mine exploded, and threw up the ground over it, its action was, at the same time, felt in a circular direction, throughout the surrounding ground, to a distance at least equal to the oblique line drawn from the centre of inflammation to the edge of the funnel.

Mines and counter-mines are now called offensive and defensive mines. The hole made by the explosion is called the entonnoir, crater, or funnel.

In the system of counter-mines, we have the magistral gallery, or gallery of the counterscarp, which is that extended below the covered way, from which branches are pushed to overthrow the works and batteries of the beseiger, that crown it; the enveloping gallery that communicates with the other passages, called the galleries of communication, and is nearly parallel with the first at the distance of from forty to sixty yards. Other galleries are pushed forward, leaving the enveloping gallery, projecting at least thirty yards, and having spaces between them of about fifty yards in width; so that the enemy's miner, whose work may be heard under ground about thirty yards, may not pass between any two of them without being discovered. These are called listening galleries. It may be observed, that, from these galleries, branches are carried forward to establish chambers under the works of the enemy. Those who wish to acquire information on this, and other subjects, connected with attack and defence, and on some branches of engineering, would do well to consult the French work of Bousmard.

There are likewise small mines called Fougasses, used in the defence of field works. They are seldom more than ten feet beneath the surface, and are placed at the expected points of attack, usually nine feet from the salient angles, and without the counterscarp. The chest of powder and the saucisson are placed as usual. Barrels or casks and even grenades are used.

Sec. XXXII. Of the Means of Increasing the Strength of Gunpowder for Mining.

We mentioned, in the article on gunpowder, that quicklime had the effect of increasing its strength. It has been suggested, to employ quicklime, for this purpose, when gunpowder is used in mining.

Bottée and Riffault (Traité de l'art de Fabriquer la Poudre à canon, p. 301) have given the result of some experiments on this subject, which we purpose to notice. These experiments, however, are not satisfactory on this head.

Dr. Baine, a physician of Foxano, in Tuscany, was the first who announced the fact, that quicklime would increase the explosive effect of gunpowder. The increase he states to be one-third. The proportions are, twenty-three grammes of quicklime, and one kilogramme of powder.[41] The quicklime is powdered, and mixed with the gunpowder.

Various experiments were made, with the eprouvette of Regnier, which did not establish the truth of Dr. Baine's assertion. The Tuscan hunters use gunpowder mixed with lime.

The experiments were made by M. L. Maitre and colonel Charbonel. They employed pure dry powder, dry powder mixed with quicklime, moist powder pure, and moist powder mixed with lime. The object of these experiments was to ascertain, if the presence of quicklime added to the force of powder; either as a fourth component part and acting chemically, or by absorbing the moisture which the powder contains.

The charge of each was three ounces.

The result of the experiments is thus given:

Powder, dry and pure,738 feet2 inches.

Powder, dry, and mixed with quicklime,690—1—

————

Difference in favor of dry powder,481

Powder, moist and pure,714feet1inch.

Powder, moist, and mixed with quicklime,642—2—

————

Difference in favor of moist powder,7111

It has been asserted, that the force of gunpowder is increased by water, alcohol, and ether, in consequence of the great expansibility of these fluids; but, according to the experiments of Bottée and Riffault, the range of the ball was much less when the three fluids were used successively, than when the dry and pure gunpowder alone was employed. We are informed by a gentleman, who saw the experiment made, that when gunpowder is mixed with an equal weight of fine saw dust, and fired, it will give the same range to a ball as the same weight of unmixed powder.

We find that col. Gibbs, (American Journal of Science, i. 87), in a letter to professor Silliman, mentions the use of lime in increasing the strength of gunpowder. He gives a certificate of the person, whom he employed in blowing rocks, in which he used quicklime along with powder, in the proportion of one part of the former to two of the latter. In the certificate, it is stated, that a charge of this mixture was found to be equally powerful, or to "answer equally well with a like quantity of gunpowder," having made upwards of fifty blasts in this manner, and, as he states, several hundred in the usual way. He remarks, however, that, when the powdered lime was mixed with the gunpowder the day before, the effect was diminished. The colonel attributes the effect to the desiccation of the powder by the lime; and, as gunpowder absorbs more or less water, the lime, in its caustic state, takes it from the powder. If the lime should remain too long, he is of opinion that it would probably attack the water of crystallization of the saltpetre, and, according to count Rumford's idea, destroy a great part of the powder. "The examination of this subject," says Gibbs, "led me to consider the increase of the power of gunpowder in various situations, and of its use in the field. It is well known, that, after a few discharges, a cannon becomes heated, and the range is much greater, as well as the recoil. The charge of powder is, therefore, reduced about one-quarter, to produce the original effect. As I have not heard or seen any explanation of this fact, I shall take this opportunity of mentioning, that it appears to arise from the same cause as the first explained, viz: the desiccation of the powder, &c."

M. Humboldt, (Bulletin de la Société Philomatique, floreal, an. 3) it appears, suggested an improvement in mining, not by increasing the force of gunpowder, but in the charging of it; to leave a space occupied only by air, a fact well known to those who are accustomed to this work, although not always adopted. He states the effect of powder on a shell; that, if it be filled, it breaks only into two or three pieces; but if only half filled, it is shattered into a great number, which he attributes to the presence of air in the shell.

Sec. XXXIII. Of Incendiary Bombs.

These are used in sieges, and on water. Ruggeri gives the preparation of these bombs as follows, observing to melt the substances in the order they are mentioned.

1. Three parts of sulphur; 2. One part of pitch; 3. Two parts of nitrate of potassa; 4. One part of mutton suet.

After melting these substances, and mixing them intimately, the mixture is removed from the fire, and two pounds of gunpowder are added, and thoroughly blended. It is again submitted to heat, and a sufficient quantity of quick match, to cover a good sized marron, is immersed. The marron is furnished with a fuse. The composition hardens on the match. The match is employed as before described. Water does not extinguish the fire, produced by the combustion of this composition. See Carcasses and Fire-Balls.

Sec. XXXIV. Of Murdering Marrons.

Marrons, which take this name, are those, whose effect is different from the incendiary bomb. The latter is calculated to set fire to houses, &c. while the former is designed to destroy the lives of persons.

To make a murdering marron, we prepare, in the usual manner, a cylindrical case, and fill it with gunpowder, and then wrap round it, a quantity of pack-thread. In winding on the thread, care must be taken to cross it in the manner mentioned in a former article. It is then finished by coating it with a mixture of glue and wax, or, in preference, pitch. This prevents the thread from unwrapping, and renders the case firm and less liable to break. A hole is then made in its side to the powder, in which we insert a piece of quick-match, to communicate fire to the contents of the case. A small fuse, similar to that of a bomb fuse, but shorter, and made of pasteboard, is also used; and, after it is fixed to the marron, musket balls, previously pierced with holes, are nailed round the marron, the nails passing through the balls into the case. After thus fixing as many balls as the surface of the case will admit, we cover them with a composition made of three parts of glue and one part of wax. When this coating is dry, a hemispherical case is adapted. This case is a small sack of paper, made round, and filled with gunpowder. It is placed at the bottom of the marron, and secured there with paper and glue. The match is conveyed to the orifice of the fuse of the marron; and, in short, a communication is so made from the one to the other, that, at a given time, the fire passes by means of the fuse to the marron, which then explodes, and throws the balls, with which it is furnished, in every direction.

Shells, made by uniting two hemispheres, containing powder, and furnished with balls and a fuse, are also a destructive weapon of the same character.

Sec. XXXV. Of Incendiary Rope.

We have mentioned, under the head of Tourteaux, or tarred links and fascines, the compositions made use of for these preparations. The composition for incendiary rope is as follows:

Sulphur12 parts

Saltpetre6——

Rosin2——

Camphor2——

Meal-powder4——

Grained powder2——

The rosin, sulphur, camphor, and saltpetre are melted, and mixed thoroughly together, and the kettle, which contains them, is removed from the fire; the gunpowder is then added, and intimately blended.

The mixture is again heated, and the rope is then immersed in it, and suffered to remain until it has imbibed sufficiently. It is then taken out, and allowed to cool.

After this operation, we melt, in a separate kettle, the following substances:

Rosin4 parts.

Pitch (or tar)4——

Mutton suet2——

When they are melted, and mixed, the rope previously prepared as above, is thrown into the mixture, and then removed and hung up.

After this second process, we make, in an earthen vessel, a priming mixture, in which the rope is sometimes immersed, or such parts of it, as are to take fire promptly. This priming paste is composed of,

Meal-powder4 parts.

Saltpetre4——

Sulphur2——

Spirit of wine, (or brandy), a sufficient quantity.

Gum arabic½——

Incendiary rope is used more generally in the form of a ball, which is enclosed in a sack, and fired out of a common mortar. It was invented by an officer at Toulon. See Carcasses.

Sec. XXXVI. Of Balloons of Grenades, of Bombs, and of Flints or Stone.

Balloons of this kind are cases, or sacks, made sufficiently large, containing powder, and enclosing grenades, shells, and stones.

The balloon of grenades holds twelve charged grenades, containing different quantities of powder. They are finished like powder sacks, and corded with small cord, twine, or thread. The balloon of flints, river stones, or small pebbles, is made by enclosing these substances along with powder in a sack, as before stated. These balloons are employed for the defence of works, &c. See Powder Sacks.

The Ballon à Bombes, of the French, is the same. It is a bag, in which are placed beds of smaller bombs, that are charged and interlaid with gunpowder. The bag is put into another covering, that is pitched, with the neck closely tied up with pack thread, in which a fuse is fixed, as in ordinary bombs. The English say, that Colonel Shrapnel's invention of the spherical case shot, is of a superior kind. We purpose, therefore, to notice them in the following section.

Sec. XXXVII. Of Spherical Case-Shot.

Ordinary case shot is a tin case or cannister, filled with iron balls, so as to make up the weight of the shot. The balls are seldom less than 1¹/₄ oz, in weight. Little effect is to be expected from firing case shot beyond 300 yards, from the very great divergency of the balls. The following summary of the effects and advantages of this species of shot, which, as invented by Col. Shrapnel, is called the Shrapnel shell, will be sufficient for our purpose. It is extracted from a book lately published.

1st. The whole charge takes effect on the enemy at any distance. By the present mode of firing, the greatest part of the charge disperses as soon as it leaves the muzzle of the gun, and cannot be directed.

2nd. Grape, or case shot, may be fired with effect equally close and collected, to any distance within the range of the piece; and the artillery need not advance within musket shot of the enemy, to make use of this kind of fire with its full effect, and are not so subject to have their guns charged either by cavalry or infantry.

3d. It requires less precision and exactness, to point a piece of ordnance charged with spherical case shot than with round shot; because case shot is a wide and dispersed fire, and the difficulty in elevation consequently less.

4th. Its comparative destruction with that of round shot will be, generally, as the number of the shot within the shells to one; that is to say, a three pounder, twenty-two to one in its favour; a six pounder, fifty to one, &c.; in which calculation is not enumerated any effect from the splinters of the shell.

5th. Small balls cannot be projected to very considerable distances, unless enclosed in heavy spherical cases, which, from their form and weight, are not much influenced by the resistance of the air, or diverted from their direction.

6th. The explosion of the shell makes no change in the direction of the shot within; they consequently complete the shell's track, or curve, which has sometimes been observed to be 400 yards.

7th. From the unevenness of the ground, such as hillocks, banks, fallow fields, &c. all shot which graze, most commonly lodge: whereas, by using this shell, the whole charge will be carried over these irregularities, and reach the object with its full contents of balls.

Sec. XXXVIII. Of the Fire-Rain, according to Casimir Siemienowicz.

The composition, which produces fire-rain, which we purpose to notice in this place, is taken from the "Artis Magnæ Artilleriæ" of Casimir Siemienowicz. He seems, however, to have taken it from a German author.

The fire rain is an incendiary fire-work, and calculated, like other incendiaries, for firing the houses of a besieged place or city, which are covered with shingles, laths, stubble, or reeds. Besides several other compositions, designated by artificers, that of fire-rain was so called from its supposed resemblance to a shower of rain.

To prepare this composition, the following method is used: We take 24 parts of sulphur, and melt in a copper, or iron pot, over live coals without flame, and then throw in 16 parts of saltpetre, and mix it with an iron spatula, to incorporate the whole. The pot is now removed from the fire, and when the composition is become rather cold, stir into it 8 parts of grained powder. The composition is then poured on a marble slab, or metallic plate, where it is allowed to cool. It is then broken into pieces of the size of a walnut, which, when used, is interspersed with quick match, covered with gunpowder, and put into shells or bombs.

These bombs are made in the same manner, as those, which are formed in fire-works for exhibition.

Wood, covered with this composition, will burn in the same manner as the shells. The globe of fire is also similar to those for exhibition. The mortar is elevated at an angle of 45°, in order that the globe may go to the greatest height, and the greatest range; for the fall of the inflamed matter, which is dispersed in all directions by the powder, is more or less vertical, and, in that state, lights upon houses, &c. This effect, that of setting fire to one or more houses, depends greatly on the accuracy of their discharge from the mortar.

The following compositions are also used for the same purpose, observing to follow the same manner of mixing the ingredients:

1.Sulphur3 parts.

Saltpetre1 ——

Meal-powder1 ——

Iron filings½ ——

Green Vitriol½ ——

2.Sulphur1 part.

Saltpetre1 ——

Grained powder1 ——

3.Sulphur1 part.

Galbanum4 ——

Saltpetre4 ——

Grained powder1 ——

4.Sulphur5 parts.

Saltpetre2 ——

Rosin1 ——

Meal-powder1 ——

These compositions may be used in the manner already described. Two wooden hemispheres, filled with the preparation and joined together, is the usual mode of forming a fire bomb. The bomb or globe is then covered with strong canvass, and finished by dipping it, or smearing it with melted pitch. Over this, two or three covers of canvass are sometimes sewed. When the bomb is dry, we put it in a case, in the same manner as directed for the murdering, and incendiary bombs. The case is charged with fine meal-powder, &c.

The modern improvements, which are many, supersede the rain-fire. Fire stone, for instance, is a more powerful preparation. The incendiaries made with this composition, and the ordinary carcass, are more effectual for this purpose. That the Greek fire was an active composition, and produced very destructive effects on towns and shipping, there can be no doubt; notwithstanding the invention of gunpowder has completely changed the art of war, and superseded, as we have shown in our articles on gunpowder and Greek fire, the use of the incendiary composition of the Greeks.

Sec. XXXIX. Of the Effect of Mirrors in inflaming Bodies at a Distance.

As this subject may be of some interest to the reader, at least in relation to an important fact, that of the concentration of the calorific rays of the sun, which has had the effect of burning bodies at some distance, we deem the following facts not irrelevant.

The effects of burning glasses, both by refraction and reflection, are noticed by Empedocles and Euclid, who composed a treatise on the ancient optics and catoptrics. It has been thought, that the Romans had a method of lighting their sacred fire by some such means. Aristophanes, in one of his comedies, introduces a person as making use of a globe, filled with water, to cancel a bond that was against him, by thus melting the wax of the seal. Plutarch, in his life of Numa, says, that the instruments used to kindle fires, were metallic dishes, which were placed opposite to the sun, and the combustible matter in the centre, by which, it is probable, he meant the focus, conceiving that to be at the centre of the mirror's concavity.

Father Kircher was the first, who thought of substituting, for a concave mirror, several plane mirrors, so disposed, that the sun's rays reflected at their surface might converge towards the same point. He employed five only of these mirrors, which he so arranged, that the concurrence of the rays should take place at a distance of more than one hundred feet, and he found the heat there to be scarcely supportable. "Now," says Kircher, "if five mirrors produce so considerable an effect, what would a hundred or a thousand do, arranged in the same manner? They would excite so violent a heat, that it would set fire to every thing, and reduce all to ashes."

Orpheus compares his jaspis to rock crystal, and says that it kindles fire, and that he knew how to use rock crystal as a burning glass. Diodorus calls some kinds of jasper transparent, and sky-coloured. The jaspis, described in the Revelation of St. John (chapter xxi, verse 11, 18, 19,) may have been the same stone.

It is not our intention, however, to notice the history of mirrors, from the time of Moses, (Exodus, chap. xxxviii, verse 8,) or of Job, (Job, chap. xxxvii, verse 18) through different periods of time, to the present day; as the reader may find an interesting account on this head in Beckman, (History of Inventions, vol. iii, p. 154); but to state in particular the celebrated experiment of Archimedes, which has indeed astonished men of science, who have lived since that period. There can be no doubt of the fact, if we reflect for a moment, that some modern experiments have justified the conclusion which has been drawn; and, therefore, that the solar rays may be concentrated to such a degree, as to inflame bodies at some distance off: and as the heat produced is much greater than that of our hottest furnaces, incredible as it may appear, there can be no question as to the effect, which may be produced by a system of mirrors.

By means of burning mirrors, Archimedes burnt the Roman ships, which were beseiging Syracuse, and reduced them to ashes.

Descartes, among others, discredited the story as fallacious; but Kircher made many experiments, with a view of establishing its credibility. He tried the effect of a number of plane mirrors, and with five mirrors of the same size, placed in a frame, he contrived to throw the rays reflected from them to the same spot, at the distance of more than one hundred feet; and, by this means, he produced such a degree of heat, as led him to conclude, that, by increasing their number, he could have set fire to inflammable substances at a greater distance. He likewise made a voyage to Syracuse, in company with his pupil, Schottus, in order to examine the place of the supposed transaction; and they were both of opinion, that the galleys of Marcellus could not have been more than thirty paces from Archimedes.[42]

Proclus is also said to have destroyed the navy of Vitalian, beseiging Byzantium, near Constantinople, by means of burning glasses.

Among the moderns, the most remarkable burning mirrors have been those of Magine; of Septala of Milan, which was nearly three and a half feet in diameter, and which burnt at the distance of fifteen or sixteen paces; of Vilette, and Tschirinhausen; the new complex one of M. Buffon; that of Trudaine, and that of Parker. Tschirinhausen's burning glass was between three and four feet in diameter, and its focus was rendered more powerful by a second one.

It may not be improper to notice the construction, as well as the effect of some of these mirrors. La Brocquire, a traveller of the 15th century, says, that, at Damascus, they made mirrors of steel that magnify objects, and one of them, when exposed to the sun, reflected the heat so strongly, as to set fire to a plank fifteen or sixteen feet distant.

M. Buffon constructed a machine consisting of a number of mirrors, by which he seems to have revived the secret of Archimedes, and to have vindicated the credit of history in this point. The experiment was first tried with twenty-four mirrors, which readily set on fire a combustible matter prepared of pitch and tow, laid on a deal board at a distance of sixty-six French feet. He then pursued the attempt, and put together a kind of polyhedron, consisting of one hundred and sixty-eight pieces of plane looking glass, each six inches square; and by means of this, some boards of beech wood were set on fire at a distance of one hundred and fifty feet, and a silver plate was melted at the distance of sixty feet. This machine, in the next stage of its improvement, contained 360 plane mirrors, each 8 inches long, and 6 broad, mounted on a frame 8 feet high, and 7 feet broad. With 12 of these mirrors, light combustible matters were kindled at a distance of 20 feet; with 45 of them, at the same distance, a large tin vessel was melted; and with 117, a thin piece of silver. When the whole machine was employed, all the metals were melted at the distance of twenty-five, and even of forty feet. Wood was kindled in a clear sky, at the distance of 210 feet. Mr. Buffon afterwards constructed a machine, which contained four hundred mirrors, each six inches square, with which he could melt lead and tin at the distance of 140 feet.

Mr. Parker, an eminent glass manufacturer, in Fleet street, London, constructed the most powerful burning mirror ever made. He erected an out building at the bottom of his garden for the purpose of carrying on his operations. He succeeded in forming a most powerful burning lens. Its diameter was three feet. Platinum, iron, steel, flint, &c. were melted in a few seconds, on being exposed to its immense focus. A diamond weighing thirty grains was reduced to six grains, in the space of thirty minutes. It opened and foliated like the leaves of a flower, and emitted whitish fumes, (carbonic acid gas;) when close again, it bore a polish, and retained its form. Garnets, clay, &c. soon melted.

Seven hundred guineas were subscribed to indemnify the inventor, it having cost him seven hundred pounds. It was purchased, however, and presented by lord Macartney to the Chinese government, and remains now at Pekin.

M. Payard, (Archives des Découvertes, &c.) has invented a burning mirror, consisting of several plane mirrors so arranged as to concentrate the solar heat into a focus with great precision. The arrangement, it may be proper to state, is different from that heretofore used, and the effect is said to be very powerful.

A polygonal mirror, from a suggestion of the celebrated Buffon, was erected in the Botanic Garden at Paris, in 1747, and had also a very powerful effect. This mirror was composed of one hundred and sixty-eight plates of tinned or silvered glass, capable of moving in every direction and of being fixed at different degrees of inclination, so that there could be given to the whole, a form more or less concave, and the focus be thrown to different distances. This mirror set fire to wood at two hundred feet, and fused metals at forty-five feet.

As caloric, like light, follows the same laws with respect to its motion, and as the angle of incidence is equal to the angle of reflection, the radiation of heat, conducted after the manner of Pictet's experiment, has not only occasioned the combustion of gunpowder, but of other inflammable substances. But, for this purpose, the mirrors must be large and extremely bright. That heat radiates in all directions, and is reflected, and that the calorific rays may thereby be concentrated, are facts which are now universally admitted. The application of this principle, by using concave mirrors sufficiently large, has, we are informed, produced the explosion of gunpowder. They were placed about twelve feet apart. In the focus of one a live coal was put, which was constantly blown with a double bellows, and in the focus of the other some gunpowder. In all our experiments with the ordinary reflectors, we could never produce any thing like the heat necessary to inflame gunpowder. That the principle is substantiated by experiment is evident; for the rays of a heated body, or a substance which produces heat, as a lamp or candle, placed in the focus of a concave mirror, are reflected in parallel lines, and if another concave mirror be placed opposite to it at some distance, the calorific rays will be thus intercepted and reflected back in a focus. This focus, therefore, like the focus of a burning glass, is the concentration of all the parallel rays of heat.

Sec. XL. Of Incendiary and Poisoned Arrows.

The bow is a very ancient weapon of offence, made of steel, wood, horn, or other elastic substance, which, after being bent by means of a string fastened to its two ends, in returning to its natural state, throws out an arrow with great force. That the bow was a weapon of offence among the nations of antiquity, the inhabitants of Asia and Africa, and the Aborigines of this country, and that it was used in Europe, before the invention or use of fire-arms, are facts, of which we have abundant proof. Bows are much the same in all countries. It has generally two inflections or bendings, between which, in the place where the arrow is drawn, is a right line. The Grecian bow was adorned with gold or silver. The Scythian bow was distinguished from those of the Grecians and other nations, by its incurvation, which was so great, as to form a half moon, or semi-circle. The Persian bows were made of reed. The Indians used the same material, as well for their bows as their arrows. The Lycian bows were made of the cornel tree; and those of the Ethiopians, which surpassed all others in magnitude, were made of the palm tree. The Romans, although they did not admit bows in the infancy of their republic; yet they considered them as hostile weapons. They employed auxiliary archers in all their wars. The Amazonians, as well as the primitive Grecians, in drawing their bow, did not pull back their hand towards their right ear, according to the fashion of the ancient Persians, and of modern ages; but, placing their bow directly before them, returned their hand upon their right breast.

While noticing this subject, we may also observe, that Louis XI first abolished the use of bows in France, introducing, in their place, the halberd, pike, and broadsword. The long bow was much in use by the English archers, and many laws were passed encouraging its use. In the time of Henry VIII, the parliament complained of the disuse of long bows.

The bow is now laid aside altogether as a war weapon. The arrows, made use of, were armed with barbed iron, and, among the aborigines of this and other countries, with a stone, formed in a particular manner, many of which are picked up in this country. We have found them at West Point. The natives were in the habit of poisoning their arrows, by using a particular composition, not known; the effect of which, however, when the arrow penetrated into the flesh, is always destructive.

Roggewein, (Voyage for the Discovery of Southern Lands) speaking of Batavia, observes, that, at this place, there are some of the Macassars, so famous for their little poisoned arrows, which they blow through a trunk. This poison is the juice of a tree, that grows in Macassar, and in the Bougie islands. They dip the points of their arrows in this juice, and then let them dry. The wound they give is mortal.

The natives of Ceylon are very dexterous with the bow and arrow; so also are the Hottentots, according to Kolben, in his Voyage to the Cape of Good Hope. A Hottentot arrow consists of a small tapering stick or cane, of about a foot and a half in length, pointed with a small thin piece of iron bearded, and joined to the stick or cane by a barrel. Their bows are made of olive, or iron wood, and the strings, of the sinews and entrails of beasts. When they attack a lion, tiger, or leopard, which they do with wonderful resolution and dexterity, they employ slings (hassagayes) and arrows, which for that purpose are usually poisoned.

Ellis (Voyage for the Discovery of a North-West Passage) speaks of the bows and arrows of the Eskimaux Indians, and the facility with which they use them, but not of poisoned arrows. Moore, (Travels into the interior of Africa) observes, that a native took him to his house, and showed him a great number of arrows, daubed over with a black mixture, said to be so venomous, that, if the arrow did but draw blood, it would be mortal, unless the person who made the mixture had a mind to cure it. For the man observed to him, that there were no poisonous herbs, whose effects might not be prevented by the application of other herbs.

Poisoned arrows, according to various historians, were used in the remotest periods of antiquity. The mode of treating wounds in the twelfth century, by using membrane like the present gold-beaters' skin, may be mentioned in relation to this circumstance. The Emperor, John Commenus, accidentally wounded himself in the hand with a poisoned arrow, while hunting, and applied a piece of skin to the wound. The emperor, however, died in consequence of the wound, after it had become inflamed under the pellicle; which, in large wounds, and when the skin is suffered to remain too long, is commonly the case, though the poison alone we are informed, would have been a sufficient cause of death. Other instances are also mentioned of death being occasioned by the poisoned arrow.

On the subject of poisoned arrows, the following outline is given on the authority of the author of the Dictionnaire de l'Industrie, vol. 3, p. 50.

The juice of the Mancenilier, or the Lianes des Marais, called in Guyanne Curare, is employed by some savages. The Arabs use the juice of a milky shrub, which they name chark, and called by the Persians gulbut samour. Indian arrows are said to be poisoned with the venom of serpents. The islanders of Java rub their darts with the blood and venom of the lizard Gecko, which they kill by whipping it to death. The needles of the Macassars, they poison with the juice of a tree, which is said to belong to the ahouai of America. At Ceylon they extract the venomous matter from the Nerium, or laurel rose. The ancient Gauls are said by M. Paw to have poisoned their arms with the juice of the Caprisiguier. In some cantons of the Pyrenees and Alps, they express the juice of the roots of the Aconitum, (thora), which they put on weapons.

M. Charles Coquebert, in a memoir read to the Philomatic Society, in 1798, observes, that the ancient European inhabitants employed three plants to poison their arrows; namely, Veratrum album, Helleborus viridis, and Aconitum Lysocitonum.

There have been obtained from the Society Islands some poisoned arrows, and a pot of the composition, in which they are dipped. It has the appearance of a black fluid extract, and seems to be an infusion or decoction of some plants, probably mixed with other substances.

With respect to the poisons obtained from the animal kingdom, they are principally liquid juices. Fontana, in particular, has paid attention to this subject. The poison of the viper, which is contained in two small vesicles of the mouth, when the animal bites, is forced, through the fangs, into the wound. If the vesicles be extracted, or the liquor prevented from flowing into the wound, the bite is harmless. Sharp instruments, as arrows, when they penetrate the skin, being covered with the poison, will have the same effect. Fontana made a set of experiments on the dry poison of the viper, and a similar set on gum arabic, and obtained the same results! Small birds and quadrupeds die immediately, when they are bitten by a viper; but to a man, the bite is not always fatal. The experiments and observations of Francini, (Abridg. Phil. Trans. ii, 8,) Mead, (On Poisons, p. 35,) Tyson, (Phil. Trans. vol. xii,) Fontana, Redi, Russel, the late Dr. Ramsay, of Charleston, (Phil. Mag. xvii, 125,) and Dr. B. S. Barton, (Amer. Phil. Trans. vol. ii, p. 100,) furnish an abundance of facts on the venom of the viper, and some on the antidotes to the bite. Dr. F. G. Gren, late professor at Halle, in Saxony, (Principles of Modern Chemistry, ii, p. 47), observes, in speaking of the experiments of Fontana, as the poison of the viper exhibits all the characteristic properties of gum, whether the gum be merely the vehicle of a peculiar venomous substance, which, upon investigation, escapes the notice of the senses? or whether this action upon living bodies, so different from its usual nature, be imparted to the gum, merely by a change in the proportions of its radicals, so slight as to be unobservable in its chemical analysis?

Mr. Misson (Travels through Germany and Italy) observes, that, at the arsenal at Venice, he saw some pocket cross bows, and steel arrows, with which the late lord of Padua used to kill such as passed by, without their knowing from whence they received their wounds.

Arrows were sometimes employed by the Grecians, for conveying their Greek fire. It seems, according to Gibbon, (History of the Decline and Fall of the Roman Empire, vol. vii, 284), that, among the different means of discharging it, that with the bow and arrow was one. For this purpose, flax or tow was dipped in the composition, and wrapped round the arrow, which was discharged the moment it was inflamed.

The Indians, and Africans in particular, have been very ingenious in poisoning several kinds of warlike instruments. The blades of swords, the barbs of arrows, balls, &c. they have prepared in such a way, as to be extremely poisonous.[43] See Poisoned Ball.

With respect to incendiary arrows, it will be sufficient to remark, that the barb, for this purpose, was furnished with a composition, which, when inflamed, was projected by the bow to the spot designed to be set on fire. They were not much employed, and at the present day, are entirely out of use. Tow, for instance, previously prepared with pitch, meal-powder, and turpentine, or a composition equally combustible, when wrapped round the head of an arrow, and thrown at the moment of its inflammation, would, in many cases, set fire to buildings. But, as the present system of employing incendiary fire-works, presents advantages decidedly in its favour, it is hardly probable, that the bow and arrow will ever be employed by civilized nations for that purpose. The ancient catapulta was particularly calculated for throwing incendiary compositions.

The catapulta was an engine, contrived for throwing arrows, darts, and stones, upon the enemy. Their power was so great, that they would project a stone of a hundred weight with an almost incredible force. Josephus, in noticing this machine, says, that the stones thrown out of it, beat down the battlements, knocked off the angles of the towers, and had a force sufficient to level a deep file of soldiers.

Sec. XLI. Of Pyrotechnical Sponge.

This name is applied to the German black match, or tinder, used chiefly to receive the file from flint and steel. We have, on a former occasion, noticed the preparation of the substance called spunk; namely, by immersing the fungus in a solution of saltpetre, and then drying it.

There are various species of agaric. The mushroom is a genus belonging to the order Fungi, and the boletus igniarius, spunk, or touch-wood, called also female agaric, is employed, not only as a match, but as a styptic. The fungous excrescences, which grow upon old oaks, ash trees, firs, &c. are all used for the same purpose. The Germans take the soft inner substance in preference to the hard, and after beating with a hammer to render it still softer, they boil it in ley, then dry it, and boil it again, in a solution of nitrate of potassa, and finally dry it in an oven for use.

The amadou of the French, is the same as our spunk, or pyrotechnical sponge. It is always made, like the latter, from various kinds of agaric, which constitute the spongy excrescence of trees. The French prepare it for use in the manner before stated. They prepare amadou, also, by soaking blue paper in a solution of nitre. They sometimes employ it in the state of tinder, and, for this purpose, burn it to a coal.

In the East Indies, there is a white spongy plant, which, when reduced to a kind of charcoal, furnishes a very good tinder.

Spunk, or pyrotechnical sponge, is generally made in Germany.

In the preparation of ordinary tinder, the best mode of carbonizing the old linen, instead of burning and then smothering the flame, is to char the rags in close iron vessels. It may be made more quick by soaking it in a solution of nitre, and then drying it.

Dry turf, or peat, is susceptible of inflammation by the spark, and, if previously soaked in a solution of nitre, the effect, we are told, is much the same as with spunk. Professor Beckman (History of Inventions, i, p. 333), remarks, that a spark falling accidentally on a turf moor, during a dry summer, often sets it on fire; and the conflagration it occasions, often lasts so long, that it cannot escape notice. Of the earth taking fire in this manner, there are many instances to be found in the ancients. One of the most remarkable, is that mentioned by Tacitus, (Annal., lib. xiii, cap. 57), who relates, that not long after the building of the city of Cologne, the neighbouring land took fire, and burned in such a manner, that the corn, villages, and every production of the fields, were destroyed by the flames, which advanced even to the walls of the city. This was certainly a morass set on fire.

Gmelin (Travels in Russia, 1768-69, vol. i, p. 22) speaks of a morass in Siberia, where a village was erected, which, on account of its situation, the inhabitants deserted. This morass was set on fire, and when he was there, had been burning for more than six months; and being very inflammable, produced much devastation.

Turf, which consists of a congeries of vegetable roots or fibres, partly in a dry and decomposed state, or partly carbonized, when separated from earthy matter, and treated in the same manner as the medullary excrescence of wood, may be advantageously employed in like manner; but it is to be remarked, that for this purpose, the small and more friable, and consequently the more decomposed part, should be preferred. That turf, or peat, has been used for fuel, from time immemorial, there can be no doubt; since it is furnished in some countries very abundantly, and its inflammability has been long known.

Sec. XLII. Of Extinguishing Flame with Fired Gunpowder.

The different methods for extinguishing fire in chimnies, by using salt, sulphur, &c. to smother the flame, as it is called, depend on one principle, that of producing either a gas or vapour, which supplies the place of atmospheric air, and as it is a non-supporter of combustion, extinguishes the flame. Carbonic acid gas would have the same effect as the sulphurous acid gas, produced by the combustion of sulphur, or the vapour of salt.

So long, however, as the air is permitted to have a draught, the fire will continue to burn; and hence, without making any remarks on the bursting of chimnies, by closing all the avenues, by which the air enters, as the fire must exert a lateral pressure, this plan is generally adopted.

It has been suggested, and in fact the suggestion is by no means new, that the smoke of fired gunpowder would extinguish flame. Some recommend firing a pistol up a chimney for this purpose, and others again, throwing gunpowder into the fire.

In the Dictionnaire de l'Industrie, iii, p. 31, I find some remarks on this subject. Besides the use of gunpowder, the vapour of water is recommended; but having some objections, among which, that of accelerating the current of air in particular, it is laid aside. Intercepting the passage of air seems to be preferred.

It appears, that the person, who first suggested the use of gunpowder for this purpose, was a Zachariah Greyl, of Augsburgh, in 1720.

The effect was attributed to the vapour of the gunpowder destroying the elasticity of the air; and the same effect is said to take place when the vapour of sulphur, or of volatile acids, is employed. It is hardly necessary to add, that this conclusion, of the diminution of the elasticity of the air, on which depends its fitness for combustion, (according to the theory then advanced), is altogether hypothetical; and the cause of the extinction of the flame, must be sought for in the substances themselves, producing an atmosphere, which is decidedly a non-supporter of combustion.

The Journal de Paris for 1785, and the Affiches de Province of the same year, recommend the use of brimstone. In the same work, page 454, it is said, that marine salt is employed with success for the extinguishing of fires; and that, when a certain quantity is thrown upon the fire, it evaporates in an instant, and displaces, by its fumes, the atmospheric air. In 1723, M. Hoffer invented his machine; and in 1781, M. Cadet de Vaux made some experiments before Leroy, Lavoisier, and Macquer, on the means of rendering bodies incombustible by saline substances, and different modes of extinguishing flame.

In 1722, the Germans announced, that, by means of a certain quantity of gunpowder, flame at all times might be extinguished. The secret, for such it was then considered, has been revived; for the same plan has lately been recommended by a modern writer. M. de Reaumur communicated to the French academy, an account of this contrivance, by which it appears, that the machine was a large box, or cask, that contained a large quantity of water; in the centre of which, was placed a case of sheet tin, containing some pounds of cannon powder. To this was attached a fuse. When it was inflamed, the gunpowder would burst the vessel, and disperse the water in every direction. See the Journal des Savants, 1725, p. 671.

In the Dictionnaire de l'Industrie, a prompt and certain method is recommended for cleaning the tunnel of chimnies. This is rather a novel plan. Of its efficacy we know nothing. It consists in taking a powder, composed of three parts of saltpetre, two parts of salt of tartar, and one part of flowers of sulphur, (or fulminating powder), and exploding it on a shovel up the chimney. The explosion indeed may detach the loose pieces of soot; but it cannot remove the harder crust, and besides, it would endanger the chimney taking fire.