Progress of Science.

What human Science has accomplished.

If we reflect on the extreme feebleness of the natural means by the help of which so many great problems have been attacked and solved; if we consider that to obtain and measure the greater part of the quantities now forming the basis of astronomical computation, man has had greatly to improve the most delicate of his organs, to add immensely to the power of his eye; if we remark that it was not less requisite for him to discover methods adapted to measuring very long intervals of time, up to the precision of tenths of seconds; to combat against the most microscopic effects that constant variations of temperature produce in metals, and therefore in all instruments; to guard against the innumerable illusions that a cold or hot atmosphere, dry or humid, tranquil or agitated, impresses on the medium through which the observations have inevitably to be made; the feeble being resumes all his advantage: by the side of such wonderful labours of the mind, what signifies the weakness, the fragility of our body; what signify the dimensions of the planet, our residence, the grain of sand on which it has happened to us to appear for a few moments!—Arago.

Changes in Social Science.

The conquests of science over the realms of matter in our day would scarcely have affected Bacon with greater surprise than the change in what we may call the social position of science. There was a time, not so very far removed from his own, when scientific truth was worshipped, if at all, with closed doors and in muffled accents. Science, like religion, had her age of persecution and her “church in the catacombs;” she, too, had heroes, and martyrs, and confessors of her own, and won her way to popularity through an ordeal of shame and suffering, the history of which remains to be written. The philosopher of the Middle Ages shunned the haunts of men; his crucible was heated in some secret or underground chamber; his knowledge was a forbidden lore, and if it showed itself in the command of new powers, was ascribed, not to inspiration from on high, but to dealings with an agent which even modern credulity so often proclaims as the source of intellectual mastery. From these fiery trials science has emerged without even a scar upon her. Militant she still is, but she is also triumphant, and vies with the learning of “letters,” which was never branded with the like infamy, in the number and dignity of her votaries. The change which has come over her social status has reacted on her doctrines. There are no longer any “mysteries” of science; “problems,” and even “apparent contradictions,” remain, but mysteries, with everything else that savours of the occult and esoteric, are exploded, and not many difficulties are admitted.—Times.

Discoverers not Inventors.

Although Galileo only discovered the moons of Jupiter, we often and unconsciously think of him as if he had been their creator, and had first set them to play their untiring game of hide-and-seek round the stately planet; and so also in no irreverent spirit we call the laws which Kepler divined to regulate certain movements of the heavenly bodies, “Kepler’s Laws,” although he disclaimed the title, grandly affirming that God, whose laws they were, had waited some thousand years before one man, even Kepler, had discerned them. And so again, notwithstanding our conviction that the star Neptune has been shining in the sky since what we shall be content to call “the beginning,” and that all the tiny planets which have so rapidly been added to our astronomical catalogues are probably as old as the sun, we cannot help feeling as if Adams, Leverrier, Hind, and their brethren, had just planted those lights in the sky, and that midnight should be sensibly less dark because of their addition to the heavens.

When we work as transformationalists we are like sculptors, not evolving a pre-existent statue from a concealing mass, but bestowing a statue on a block of marble. The hollow screw is Archimedes’ screw; the condensing steam-engine, Watt’s engine; the railway locomotive, Stephenson’s locomotive; the electric telegraph, Oersted’s telegraph; the Crystal Palace, Fox and Paxton’s palace. Yet as implied in what has been already said, we treat discoverers as if they were inventors, and to make amends we call inventors discoverers. And although, in strictness of speech, it is inadmissible to speak of Watt, as accomplished men are frequently found doing, as the discoverer of the steam-engine, and only Sancho Panza thought of invoking blessings on the man who first invented sleep, still the popular confusion between the discoverer and the inventor shows how difficult it is to assign the one higher praise than the other.—Prof. George Wilson.

Science of Roger Bacon.

Roger Bacon, writing about the year 1260, that is, six hundred years ago, says:—“I call that Experimental Science which neglects argumentation; for the strongest arguments prove nothing as long as the conclusions are not verified by experience. Experimental science does not receive truth at the hands of superior sciences. It is itself mistress, and other sciences are its servants. It has, in truth, the right to command all sciences, since it alone certifies and sanctions their results. Experimental science is, therefore, the queen of sciences and the limit of all speculation.” The features in Bacon’s writings that have caused his name to be handed down as a founder of physical science are very obvious. He doubts wisely and has a profound reverence for facts. The theory of a vacuum has come to him on the highest authority, but its difficulties distress him. He speaks of experimental philosophy as more perfect than all the natural sciences; “for it teaches us to test by trial the noble conclusions of all the sciences, which, in the others, are either proved by logical arguments or are examined into on the imperfect evidence of nature; and this is its prerogative.”

“As a workman in the laboratory, and with lenses, he himself discovers the existence of explosive compounds, confirms the tradition of history as to the effect of burning glasses, and understands the principle of the camera. He points out the faultiness of Cæsar’s calendar. His views of the limits of medicine are excellent. ‘For, whereas a healthy rule of life depends upon what is eaten and drank, on the hours of sleep and waking, of exercise and rest, on climate and the temper of the mind, and that all these should be observed from childhood in the constitution they fit, scarcely any man cares to take thought of these things, nay, not even physicians, such at least as we have met with.’ Contrast this and his critical approval of the use of charms to delude credulous patients into health with the science ridiculed in the Malade Imaginaire, and the advantage will not be found on the side of the seventeenth century. But, even in physical science, Bacon’s splendid powers of generalization prevail over the habit of analysis, and he is rather a prophet than a teacher. He believes that the period of human life may be prolonged many years by a sound system of dietetics; and the averages of life in our own century confirm him. He believes that ‘engines of navigation may be made without oarsmen, so that the greatest river and sea-ships with only one man to steer them, may sail swifter than if they were fully manned. Moreover, chariots,’ he thinks, ‘may be made so as to be moved with incalculable force without any beast drawing them.’ ‘And such things might be made to infinity, as, for instance, bridges to traverse rivers without pillars or any buttress.’ He even knows a wise man who has determined to construct a flying machine; but Bacon’s tone on this subject is a little less confident. That he himself hoped for much that has since been proved impossible—for the art of increasing gold, and for the discovery of an elixir of life—cannot of course be questioned. Bacon summed up the science of his times, and the analogies which guided him in his estimate of the laws of motion could not teach him to anticipate by five hundred years the individuality of the elements, or to understand the texture of the human body. His error, after all, was chiefly that he believed in Thought as a conqueror, and expected to establish her kingdom on the ruins of the thrones of the visible world.”—Saturday Review.

The One Science.

In an able summary in the Times of the contents of Sir Henry Holland’s Essays on Scientific and other Subjects, we find the following suggestive passages:—“The sciences are so interlacing and coalescing that it would seem as if in a year or two we should only have one huge science embracing all; or, at least, what are now regarded as separate sciences should be considerably reduced in number. This is more or less implied in the controversy on the “Correlation of Forces.” The question is,—Are there really “Forces” in nature? Or should we not rather say that there is but one force appearing under different forms? Among these forces may be mentioned light. The undulatory theory of the transmission of light is as old as Huyghens, but its universal acceptance is an incident of our own day; and it is in our own day that radiant heat has been discovered to be subject to those great physical laws which are the basis of the undulatory theory. Here, then, we find in our time, within the last few years, that the three great sciences of optics, of acoustics, and of heat, reduce their principal facts to the same formula. Or again, take this science of optics in another relation. It has within the last few years proved itself to be the most delicate instrument of chemistry. By the aid of a little starch the chemist can detect the millionth part of iodine in solution. Mr. Faraday has found that a strong ruby tint is given to a fluid by a proportion of gold not exceeding the half-millionth part in weight. These are wonderful results of ordinary chemical analysis; but what are they in comparison with the results obtained through the analysis of the spectrum? By means of it chymists have been able to detect in a compound 1-70,000,000th part of a grain of lithium, and the 1-180,000,000th part of a grain of sodium, the metal of common salt. The method of the analysis is very simple. If a little sodium, for instance, be burnt in a flame, and during the process of this burning the rays be made to pass through a prism, then in a certain defined portion of the spectrum beyond there will appear a thin yellow line, so vivid that it will show even when the sodium has been reduced to the 1-180,000,000th part of a grain. By help of the same analysis we pass on to astronomy, and discover the chemistry of the sun, the moon, and the stars. In the photosphere, or luminous atmosphere surrounding the body of the sun, there has in this way been discovered no less than six known metals.

“In these few examples we indicate roughly but sufficiently the intimate connexion of the physical sciences, and the necessity which is imposed on the student in the present day to know all if he would understand one. It has been said that he who has seen but one work of ancient art has seen none, while he who has seen all has seen but one. We may say the same of science. To know one is to know none, and to know all is to know but one.”

Sun-force.

Daily the conviction deepens among those who have studied the matter, that with a few exceptions all the physical powers which man wields as movers or transformers of matter are modifications of Sun-force. It was bestowed upon antediluvian plants, and they locked it up for a season in the woody tissue which it enabled them to weave, and afterwards time changed that into coal; and the steam-engine which we complacently call ours, and claim patents for, burns that coal into lever-force and steam-hammer power, and is in truth a sun-engine. And the plants of our own day receive as liberally from the sun, and condense his force into the charcoal which we extract from them, and expend in smelting metallic ores. With the smelted metals we make voltaic batteries, and magnets, and telegraph wires; and call the modified, sun-force electricity and magnetism, and say it is ours, and ask if we may not do what we like with our own.

And again, the plants we cultivate concentrate Sun-force in grass, hay, oats, wheat, and other fibres and grains, which seem only suitable to feed cattle and beasts of burden with. But by and by a Spanish bull-fighter is transfixed by this force, through the horns of a bull, and dies unaware of his classical fate, pierced to the heart by an arrow from Apollo the Sun-god’s bow. On English commons prizes are run for, by steeds which are truly coursers of the sun, for his force is swelling in their muscles and throbbing in their veins, and horse-power is but another name for sun-power. Nor is it otherwise with their riders; for they too have been fed upon light, and made strong with fruits and flesh which have been nourished by the sun. His heat warms their blood, his light shines in their eyes; they cannot deal a blow which is not a coup-de-soleil, a veritable sun-stroke; nor express a thought without help from him.

In grave earnestness, let me remind you, that as force cannot be annihilated any more than matter, but can only be changed in its mode of manifestation, so it appears beyond doubt that the force generated by the sun, and conveyed by his rays in the guise of heat, light, and chemical power, to the earth, is not extinguished there, but only changes its form. It apparently disappears when it falls upon plants, which never grow without it; but we cannot doubt that it is working in a new shape in their organs and tissues, and reappears in the heat and light which they give out when they are burned. This heat, which is sun-heat at second hand, we again seem to lose when we use plants as fuel in our boiler-furnaces; but it has only disguised itself, without loss of power, in the elasticity of the steam, and will again seem lost, when it is translated into the momentum of the heavy piston, and the whirling power of a million of wheels.

The second-hand heat of the sun appears equally lost when vegetable fuel is expended in reducing metals; but oxidize these metals in a galvanic battery, and it will reappear as chemical force, as electricity, as magnetism, as heat the most intense; and, in the electro-carbon light, will return almost to the condition of sunshine again.—Prof. George Wilson.

“The Seeds of Invention.”

Sir William Armstrong maintains, as a half-truth, that Invention is the fruit of the circumstances that call for it almost more than of the mind from which it springs. In a sense it is true, as Sir William Armstrong says, that “the seeds of invention exist, as it were, in the air, ready to germinate whenever suitable conditions arise;” but it depends not the less on the genius of individual inventors to determine whether the germination shall happen in one century or the next. The history of the locomotive is itself the strongest argument against relying too much on these floating seeds of invention and favouring circumstances, and taking too little account of inventors. If the Killingworth brakesman had died in his youth, it is scarcely too much to say that we should probably not yet be travelling by steam. We owe it to George Stephenson’s keen insight and resolute temper that the locomotive was forced upon an unbelieving world, no one can say how long before circumstances would otherwise have called it into existence. The seed had been floating, it is true, and had been in a manner detected centuries before; but it remained without life, not because the occasion had not called it forth, but because the right man had not arisen.

The Object of Patents.

The recklessness with which Patents are issued, and the dishonesty on the part of the State in selling the same article to two or more persons, and then coolly leaving them to litigation for the possession of it, cannot be too strongly reprehended. The common sense of the question is summed up by Dr. Percy, in these words: “I cordially subscribe,” says the Doctor, “to the opinions expressed by Mr. Grove, Q.C.—namely, that the real object of Patent Law was ‘to reward not trivial inventions, which stop the way to greater improvements, but substantial boons to the public; not changes such as any experimentalist makes a score a day in his laboratory, but substantial practical discoveries, developed into an available form.’”

The law with respect to Patents has been greatly simplified and improved by the statute 15 and 16 Vict. c. 83: the fees payable for a Patent have been reduced, and the payment of spread over several years. One Patent now suffices for the United Kingdom, and is no longer void, as formerly, for trifling inaccuracies in the Specification, as these may be now disclaimed.

Before quitting the subject of Patents it may, perhaps, be serviceable to call attention to the admirable Abridgments of Specifications now publishing by the Patent Commissioners. In a few minutes one can get exact information there which cannot otherwise be obtained in as many hours. These Abridgments are in the form of small 8vo volumes.

Hereafter we hope to see provided out of the revenues of the Patent-office, a public library and museum, to constitute a historical and educational institution for the benefit and instruction of the skilled workman of the kingdom. Exact models of machinery are to be exhibited in the subjects, showing the progressive steps of improvement.

Theory and Practice.—Watt and Telford.

James Watt was a highly accomplished theorist, on every point on which he worked; yet his name has been frequently cited, as a proof that theory could be dispensed with. And his career, when compared with that of Telford, will illustrate theory applied to practice, as distinguished from practice alone, however acute. It is impossible to contemplate the career of Telford without a feeling of high interest, created by the comparison of his apparently inadequate education with his startling successes. Looking at the individual himself, there is everything for his age to admire; and as long as his structures last, each of them is the monumentum, but not ære perennius. The time will come when his name shall be like that of the builder of the old London bridge, who was, no doubt, the Telford of the day,—a stimulus to his contemporaries, useful and honoured, but not the remembered of succeeding ages. On the other hand, the discoveries of Watt, though equally startling in what is called the practical point of view, have the mind of the discoverer impressed upon them, and have been, and must be, the guide of his successors, not merely to repetitions of what he did himself, but to the enlargement of ideas, and the conversion of principles into forms useful in art. Take away the honourable qualities which enabled the two men to outstrip their contemporaries, each in his line; qualities which are the properties of the individual minds, and consider what is left, namely their modes of proceeding: consider the effect of these two modes on men in general, and there is nothing in that of Telford which would raise a workman above a workman; while in that of Watt there is the vital principle to which we owe all the mechanical triumphs of civilization, and all the theoretical successes of philosophy.—Penny Cyclopædia.

Practical Science.—Mechanical Arts.

It seems impossible to exclude from a review, however slight, of contemporary progress in the exact Sciences, the advantages which have accrued to them, both directly, and as it were reflexively, by the astonishing progress of the Mechanical Arts. The causes, indeed, which called them forth are somewhat different from those which are active in more abstract, though scarcely more difficult, studies. Increasing national wealth, numbers, and enterprise, are stimulants unlike the laurels, or even the gold medals, of academies, and the quiet applause of a few studious men. But the result is not less real, and the advance of knowledge scarcely more indirect. The masterpieces of civil engineering—the steam-engine, the locomotive-engine, and the tubular bridge—are only experiments on the powers of nature on a gigantic scale, and are not to be compassed without inductive skill, as remarkable and as truly philosophic as any effort which the man of science exerts, save only the origination of great theories, of which one or two in a hundred years may be considered as a liberal allowance. Whilst, then, we claim for Watt a place amongst the eminent contributors to the progress of science in the eighteenth century, we must reserve a similar claim for the Stephensons and the Brunels of the present; and whilst we are proud of the changes wrought by the increase of knowledge during the last twenty-five years on the face of society, we must recollect that these very changes, and the inventions which have occasioned them, have stamped perhaps the most characteristic feature—its intense practicalness—on the science itself of the same period.

It has long been the fashion of one party to lament “the Decline of Science” in England; whilst another section has gravely declared that Science in this country is but the growth of yesterday, having been imported from Germany, and tenderly nurtured by the magnates of the realm. In the House of Commons, in the Session of 1863, a member stood up, and, with exultation, announced that Science had at length found its way into that democratic assembly through the individual exertions and influence of one now no more. From the language which this scion of a great house employed it might be inferred that Science had been previously almost unknown in England. The member, no doubt, spoke according to his knowledge; but it possibly escaped his memory that a man named Isaac Newton once existed. Without justly exposing ourselves to the charge of presumption, we might also boast of a few other names of distinction among the dead as well as the living.

There is another point upon which the public appear to be much misinformed—namely, that Science is in the receipt of large sums from the State. The annual amount voted out of the taxes for Science and Art is unquestionably large; but it should be borne in mind that, comparatively, only a small portion is really devoted to Science, while Art takes the lion’s share. Let it be so by all means. True Science to be worth anything must never become the creature of State bounty. We want no Institute with its salaried members and its eternal jobbing. We need no patronizing Mecænas, whether from the high-born or the self-exalted. What Science earnestly desires is to be let alone, that she may follow her destined course quietly, modestly, and without molestation. She especially loathes the Pythonic embrace of meddlesome persons who, knowing nothing of her, yet profess an intimate acquaintance with her and a tender regard for her welfare, solely with the object of puffing themselves into notoriety. She disdains them utterly.—Times journal.

We hear much, too, of “Science and Art” now-a-days coupled together, as if the strongest affinity existed between them; although no two things can be more unlike each other. The Arctic Circle and the Torrid Zone cannot be wider apart or in stronger contrast; for Science is frigidly logical, and Art hotly emotional.

Force of Running Water.

It has been proved by experiment, that the rapidity at the bottom of a stream is everywhere less than in any part above it, and is greatest at the surface. Also, that in the middle of the stream the particles at the top move swifter than those at the sides. This slowness of the lowest and side currents is produced by friction, and when the rapidity is sufficiently great, the soil composing the sides and bottom gives way. If the water flows at the rate of three inches per second, it will tear up fine clay; six inches per second, fine sand; twelve inches per second, fine gravel; and three feet per second, stones of the size of an egg.—Lyell’s Geology.

Correlation of Physical Forces.

Of late years experimental philosophers have been occupied with the investigation of a profound problem. Formerly, the most brilliant phenomena of nature were attributed to the existence of imponderable fluids. But the Correlation of heat, light, electricity, magnetism, and chemical affinity, as varying manifestations of force, attributable to modifications of motion in matter, now employs our subtlest thinkers—Faraday and Grove, Wheatstone and De la Rive. These researches extend even to the confines of the moral phenomena. The chemistry of nature differs from that of the laboratory, and the difference has been attributed, not simply to organization, but to the vital force—a power found only in living organisms. Yet, at length, the laboratory of Hoffman imitates the processes of nature, especially in plants, and produces some of the most delicate of the perfumes of flowers and fruits, and even seems on the very verge of the manufacture of some of its greatest treasures—such as quinine. Some are staggered by the steady march of scientific research into the most sacred sanctuaries of life, and recoil from investigations which trace the growth of the cell in the ovary into the perfect man; as though mystery were essential to faith; or, if it were so, as though there is the slightest risk that in ages to come man will have so stolen the sacred fruit that no mystery will remain to be solved.—Sir James Kay Shuttleworth on Public Education.

The Effect of Oil in stilling Waves.

It was thought that this old idea had been completely disproved by experiment; but, according to the Saturday Review, the very contrary has been the result of recent experiments, in course of which, at all events, waves on a pond, generated by the wind, were completely stilled to a “glassy smoothness” by means of a film of oil scarcely more than the 7,000,000th part of an inch in thickness, and exhibiting the most brilliant zones of iridescent colours from its extreme thinness. The modus operandi is believed to consist simply in the wind ceasing to have a hold upon the water by the intervention of the oil, which slips along the surface with the wind, so that the oil must be applied to windward, and it moves to leeward, smoothing the surface as it goes!

Spontaneous Generation.

Of all errors upon the formation of beings, the most absurd is Spontaneous Generation. Yet it is one of the most popular. If this theory is admissible for inferior beings, such as intestinal worms, infusoria, or polypi, why not for superior beings? The difficulty becomes an impossibility in both cases. Can it be imagined that an organized body, of which all the parts are intimately connected, with an admirably contrived correlation, so full of profound wisdom, is produced by a blind assemblage of physical elements? The organized body must have derived its existence from elements of which it was destitute! Then motion might proceed from inertia, sensibility from insensibility, life from death!

Guano.

In Mr. Ross’ translation of Dr. Tschudi’s Travels in Peru, 1847, we are informed that the correct orthography is Huanu, and not Guano. He states that it is a term in the Quichua dialect, meaning “animal dung.” As the word is now generally used it is an abbreviation of Pishu Huanu, bird dung. “The Spaniards,” he says, “have converted the final syllable nu into no The European orthography Guano, followed also in Spanish America, is quite erroneous, for the Quichua language is deficient in the letter G, as it is in several other consonants. The H, in the common formation of the word, is strongly aspirated, whence the error of the orthography of the Spaniards, who have sadly corrupted the language of the Autochthones of Peru.”

What is Perspective?

Perspective is the science which furnishes us with the laws by which we can give the apparent, as geometry those by which we can give the real, forms of objects. These laws are obvious without rules to thoughtful, artistic common-sense—but, to many, books on the subject will always be useful, if not indispensable. The science was called perspective, or seeing through, from an impression that the correct foreshortening of objects could be gained by viewing and tracing them through a pane of glass. This plan only ensures correctness when the plane of the eye is parallel to that of the medium upon which the drawing is made. A picture in perspective is simply a plane parallel to the plane of the eye intersecting the rays that come from the surface of the objects represented. The points of these rays at the places of their several intersections combine to form the true perspective representation. This was the art that Mantegna made so much of at Padua; and that with which Bellini, the painter of the National Gallery “Doge,” delighted the Venetians. Without much semi-scientific pedantry, the whole science may be understood by balancing a half-crown on the top of the forefinger of your right hand. Hold it up so that its broad plane is parallel to the eye’s plane; put it nearer or further, and it seems to increase or diminish in size. Turn it obliquely, and it appears an oval; put the edge on a line with the eye, and it appears a mere thin straight line. A sphere is the only geometric form that undergoes no perspective changes. The eye is able to take in any given space set at an angle of under sixty degrees. When both eyes view a scene, instead of the circle one eye sees, we have an ellipse formed by the continuation of the two circles of vision,—the point of sight being opposite the centre of the space between the two eyes. Perspective is of great use in Art; but the books upon it are too abstruse, and imply a knowledge of mathematics. [This common-sense explanation is from the pen of Professor Wallace, M.A., in the first number of a journal edited by him and entitled The Public Instructor.]

The Stereoscope.

Till the discovery of the Stereoscope, naturalists were puzzled to account for a single image resulting from double vision; and Gall and Spurzheim endeavoured to explain it by the supposition that one eye only was active at a time, the other only admitting light, and that Nature had given us two merely to provide against the accidental loss of one.—Leslie’s Handbook.

Burning Lenses.

The danger from Lenses, when the heat of the sun is powerful, is well known. As an illustration, we may relate an instance which occurred on the premises of Messrs. Negretti and Zambra, philosophical instrument makers, in Hatton Garden. There was a smell of fire, but it could nowhere be detected, until a person entered the shop from the street with the startling information that the window was on fire, and such was really the fact: a large reading-lens hanging in the window exposed to the sun, its focus happening to be just within range of the woodwork of the window fittings, set fire to them, and no doubt in a very few seconds some serious damage would have been caused. Is it not possible that in tropical climates, when vessels are becalmed, they may be set on fire by the eye-deck lights everywhere observable on ships’ decks; or, nearer home, in warehouses, &c., where such means of lighting is resorted to? The matter merits serious consideration and should serve as a caution.

How to wear Spectacles.

In the proper use of Spectacles there is no circumstance of more importance than their position on the head. They should be worn so that the glasses may come as close to the eye as possible without touching the eyelashes; they must also be placed so that the glasses may be parallel to the paper when held in an easy position. To accomplish this, let the sides of the spectacles bear upon the swell of the head, about midway between the top of it and the ear; the eyes will then look directly through the glasses to the paper, and make the most advantageous use of them, instead of looking obliquely through them to the paper, as in numerous cases, where persons place the sides of their spectacles in contact with, or very near, their ears—in which position they produce a distorted image on the retina. The sides of the spectacles should also be placed at an equal height upon the head; and the hands being applied to the points of the sides, will generally direct their equal height, as well as allow of their opening to the full extent without injury.—Adams on the Human Eye.

Vicissitudes of Mining.

Although the thoughts of men have been turned to the mineral conditions of these islands for more than two thousand years; and in that period the art of Mining has improved; and the engineering appliances which have been brought to bear upon the ventilation and the draining of mines, are fine examples of mechanical ingenuity,—the science of Mining, however, can scarcely be said to have, as yet, any existence. In 1856, Mr. John Taylor, who must be regarded as a good authority, stated before a Committee of the House of Commons, “That there were no greater facilities for ascertaining the productive character of a mine now than formerly. The difference was simply in improved machinery. Our knowledge was not greater than that of our forefathers.” Whatever was said in 1856, is true at the present moment.

The psychological influences of subterranean toil form a strange but interesting subject of study. These and the effects of that continued uncertainty as to the reward which labours of the severest kind are to receive, are distinguishingly marked on every miner. In occult powers they are believers; and when, about a century since, the “Divining Rod” was introduced into Cornwall as a means for finding mineral lodes, it was eagerly seized upon; and, to the present day, several families are supposed to possess remarkable powers as diviners, or, as they are commonly called, “dowsers.”

Mr. Rawlinson observes that the existence of “diviners,” or “dowsers,” for finding out the mineral lodes was a serious reflection upon the present age; yet it was a curious fact, that a French adventurer, who was supposed to have been successful in finding water-beds in Africa, was introduced to the Government during the Crimean war, and was sent out to trace, by the divining-rod, water in that locality.

The most elementary laws of science are still a book sealed to the large majority of miners, and while they are, of all men, themselves the most theoretical, they always meet any attempt to explain phenomena upon the evidences of inductive research, by pronouncing the explanation to be a “theory,” which is of no value to a “practical.”

Mr. Wallace, himself a miner, says: “The impossibility of arriving at any knowledge of practical value respecting ore deposits in veins, is avowed by those who, with singular inconsistency, attach the greatest importance to individual experience. Even some occupying high distinction as directors or proprietors of mines, affirm, without qualification, that it is impossible to see through solid rocks.”

It must be admitted that amongst the miners there is an entire absence of any method by which a knowledge may be obtained of the causes leading to the production of mineral deposits; while the speculations of those philosophers who will not endure the toil of subterranean investigations are wild, and are consequently valueless.

The natural consequence of this imperfect knowledge is, that all mining speculations are necessarily attended with much uncertainty. From time to time a most productive mine is discovered. The Devon Great Consols, first known as Huel Maria, has paid 826l. dividends upon every share, one pound only being paid for shares now worth 490l. each. Upon the shares of South Caradoc, near Liskeard, the trifling sum of 25s. only was ever paid; the price of these shares, in 1862, was 390l.; and 391l. profit had been paid on every share.

There are other examples of great success in mining. Such results as these are laid hold of by designing men, and used to bait the hooks by which those who are in a hurry to be rich are caught. Permission to search for minerals is obtained from the possessor of the land near to some productive mine. A few trials are probably made, and then comes the formation of a company to work “Huel Chance” (or some more attractive name is adopted), through which the lodes from the fortunate neighbour are shown, by the aid of a parallel ruler, to run.

Mr. Rawlinson states, with regard to the pecuniary losses incurred in mining speculations, that some years ago, whilst holding an official inquiry in Cornwall, he was brought into connexion with several of the large mining adventurers of that district; and they stated it as their opinion that, if the value of all the ore mines in Cornwall, and the cost of working them were compared, the statement would stand as something like 25s. paid for every pound’s worth of ore obtained.

Statistics show that about 350,000 persons are employed in the production of minerals, to the value of nearly 35 millions per annum, which gives, as the production of each miner, not more than 2l. per week, an amount so small that we can hardly conceive it possible that it would remunerate the large capital which is invested in these mines.—See Mr. Robert Hunt’s valuable Report, 1862.

Uses of Mineralogy.

Professor Tennant states there have been already described 500 minerals, more than half which number are found in the British Isles; whilst more than 450 are found in our colonies. In the International Exhibition of 1862, our vast colonial mineral wealth was shown in remarkable specimens of gold, silver, copper, precious stones, &c., many of which had been found by working miners who had been sent out from this country. Yet, miners are generally ignorant of the value of minerals, which they reject as not worth collection: now, the gold they collect is worth 4l. per ounce; but rough stones are often rejected, which are worth 50l. per ounce, and some 500l. per ounce—they are diamonds. Mr. Tennant believes that, in many of our colonies, these minerals are thrown away, whereas a little knowledge of the use of the blowpipe would enable miners to distinguish one substance from another.

Our Coal Resources.—The Deepest Mine.

Professor Morris describes the carboniferous series of rocks in England which contain Coal as deposited above the old red sandstone, or what have been called the Devonian rocks, and several thousand feet in thickness, though the coal measures are of much more limited depth, and the mines of coal vary from thirty feet to only two inches thick. The distribution of Coal in England is much greater than in any country in Europe; though in the United States of America, near Pittsburg, the beds of coal extend over a vast area, and one is of great thickness. The quantity of coal that is raised from the pits in this country, however, exceeds that from all the other coal-fields in the world.[14] The probable duration of coal in England has formed an interesting subject of speculation with some geologists, who have estimated the period variously at from 300 to 1000 years. Sir William Armstrong, at the Meeting of the British Association, in 1863, estimated the minimum period of the northern coal-field at 200 years; but Mr. N. Wood, the great coal-viewer of the North, is of opinion that of the northern coal-field no conjecture, of practical utility, can yet be formed, as more than one half of the basin, lying under the sea, has not yet been explored.

Sir William Armstrong’s remark, however, was misunderstood, and thought to refer to the coal supply of the whole kingdom, whereas he limited the remark to the coal-field of Durham and Northumberland. This misapprehension re-opened the question of the exhaustion of our coal resources, and led to the communication of some valuable evidence to the Times journal. Thus, Mr. E. Hull, of the Geological Survey, states as the result of a series of investigations of the British coal-fields, that adopting the limit of depth at 4000 feet, he found there to be enough workable coal, at the rate of consumption for that year, (about 71,000,000 tons,) for nearly 1000 years; and even if the consumption should ultimately reach 100,000,000 of tons, that supply could be maintained for 700 or 800 years.

With respect to the assumed depth, 4000 feet, Mr. Hull adds:

“Already a depth of nearly 1000 yards has been reached in a Belgian colliery, and coal is now being extracted from depths of 700 and 800 yards in Lancashire. Even with the vertical limit of 4000 feet, I have since found reason to believe that the estimate I arrived at in the case of the South Wales coal-field was rather under than over the truth. In that coal-basin alone, with an area of 906 square miles, I calculated that the rate of consumption for 1859, of 9½ millions of tons, could be maintained for 1600 years; but it is only right to state, that Mr. H. Vivian, M.P., in a pamphlet published by him in 1861, controverts this view, and arrives at the conclusion that ‘South Wales could supply all England with coal for 500 years, and her own consumption for 5000.’

“As regards the absolute quantity of mineral fuel in this island, it may be considered as practically inexhaustible. The seams of coal outcrop in our coal-fields, and descend under the Permian and Triassic formations to depths exceeding 10,000 feet. The question of the available supply is therefore one depending on the rapidity of production and the limit of depth.”

Dr. Buckland, in 1841, dwelt upon the wanton waste of coal at the pits, which, in 1836, he had maintained would finally “exhaust the Newcastle coal-field at a period earlier by at least one-third than that to which it would last if wisely economized.” The waste has, however, been much abated.

Mr. Robert Hunt, however, maintains the consumption to be greatly understated. He says:

“All calculations on the probable duration of our coal-fields have been founded on the very erroneous data which supposes that not more than 36,000,000 of coals are raised annually. We know that more than sixty-six millions of coals are now annually produced, and the demands upon our resources are rapidly increasing.”

Sir William Amstrong himself quotes Mr. Hunt as showing “that at the end of 1861 the quantity of coal raised in the United Kingdom had reached the enormous total of eighty-six millions of tons, and that the average annual increase of the eight preceding years amounted to 2¾ millions of tons.”

If, therefore, Dr. Buckland’s remarks were important in 1836 (when his Bridgewater Treatise was first published), and of “greater force” in 1858, how much more must they be worthy of most serious consideration in 1863.—Communication to the Times by Mr. Frank Buckland. Another Correspondent, however, adds this consolation:

“There may yet remain plenty of coal in the world. Three-fourths of the globe are covered with water, and what geologist shall presume to declare that there are no vast deposits of coal deep below the ocean bed? We have been up and down below the waters several times, and we shall probably sink again; but then the bed of the Atlantic may become dry land and peopled with our successors. Change is the law of the universe. The moon is stated to be approximating to the earth at the rate of a fraction of an inch in a century or so, and may one day come tumbling upon us. The whole of the solar system seems to be travelling—some report at the slow rate of 47,000 miles an hour—towards an unknown region of infinite space. Great Britain, therefore, has no reason to complain if she shares the common fate of all things, whether in the heavens above or on the earth beneath.”

Monkwearmouth, Sunderland, is the deepest coal-mine in all England; the coal being won at nearly two miles’ distance from the shaft, and upwards of 1900 feet, or more than five times the height of St. Paul’s, below the surface of the green fields and trees above. The pit employs nearly 300 hands, and yields between 500 and 600 tons of domestic coal per day; every few seconds, the tall cage shoots up out of the gloom of the shaft, and the tubs, like miniature railway-waggons, holding nearly half a ton each, are brought to the bank, and wheeled away in different directions. Not for a single instant does the work stop: it is coal—coal everywhere beneath and around; the very atmosphere is made gloomy with its fine particles; and all this, seen amid clanking of chains, roaring of steam, and the rapid activity and whirl of hurried business, make it one of the most curious and interesting scenes imaginable.

The dangers of the working are thus detailed. The boys in charge of the trams carry the “Davy,” the wire-gauze of which is far less liable to injury than the glass shade of the “Geordie,” or Stephenson lamp; and with these the lads may safely pass the “goafs” or worked-out seams, in which, though built up as far as possible, gas always lurks, though the invisible enemy around them is so thick that the gas will light inside their lamps and burn with a ghastly blue flame. Beyond this steep incline or bank there is still nearly a mile to be traversed to the “in-bye”—the face of the working, the spot from which the coals are actually won: where, too, the gas has its head-quarters, and has to be watched and guarded against every hour and minute of the day and night, for the work of a mine never stops, and day and night are meaningless terms in such eternal gloom and silence. The heat at the bottom of the bank, indeed in all parts of the mine, is very great in the extreme depths of Monkwearmouth. It is seldom less than 84 or 85 deg., and at the workings often over 90 deg. So great is the heat, in fact, that the men nearly always work almost naked, and in some cases absolutely so. The heat certainly does not arise from want of proper ventilation, which seems ample. Not much bratticing is used to convey the air through the workings, and it is almost entirely confined to the places where the coal is won. In fact, as far as human ingenuity, skill, or experience can go, the pit is made safe from gas at least. Its only risk seems to be from shaft accidents or inundation, to both of which more or less all colleries in this district and near to the sea are, to say the least, equally exposed and equally protected against, as far as it is possible to do it.

Iron as a Building Material.

The late Professor Cockerell, in a lecture on Architecture, at the Royal Academy, observed upon the early employment of this material in building:

The progress of architecture depends as much on discovery of new materials and new methods of building as on taste. Iron was used by Tubal Cain as a subsidiary material. It has been employed in building ever since; but never in solid and in the gross as a constituent part of the substance of building before Mr. Rennie employed it as voussoirs in the Southwark Bridge. Sir Robert Smirke has nobly followed in applying iron in trabeation, and so has Mr. S. Smirke in the new reading-room of the British Museum, and others; but the engineers have kept ahead of the architects, from Mr. Rennie to Messrs. Stephenson, in displaying the powers of iron.

Iron has been cited in Deuteronomy as the essential and last fruit of the promised land. Our interiors, as halls and churches, will assume new development and grandeur by iron, since we have seen 200 feet span at Birmingham without abutment, and 150 feet at Paris in still more enduring structure. The Pantheon of Rome, Sta. Sophia, St. Peter’s, the Baths, and the great Riding-house at Moscow, will hide their glories; and iron will henceforward dispense with pillars and clerestory, flying buttresses and abutments, and roof our churches in bold and single spans. With all due reverence for antiquity and precedent, we ought to open our eyes to the reconciliation of this new material and its peculiar faculties with the laws of proportion and taste; and this is a problem worthy of the best spirits, both as to the form of roofs or ceilings, and the form of supports, which, in iron, with 1-40th part of substance of stone, will give equal strength of support.

Iron may be termed the osteology of building. Hitherto the architectural system has proceeded on statics and equipoise of molecules, as if the human frame were built without bones. Now our buildings will have bones, giving unity and strength which never before existed. The nervures of the Gothic will now be in uniform and single arcs, erected at once: the library at St. Généviève, by Mons. Arbruste, exhibits an experiment in this way.

Concrete, not new.

Professor Cockerell observes:—Concrete is a novelty characteristic of the nineteenth century, or rather a resuscitation of ancient practice, as shown by quoting Philibert de l’Orme; but in the bridge of Alma, at Paris, concrete has taken a new and admirable development, where three arches of about 140 feet span are cast on the centreing, forming one vast stone from pier to pier. The only voussoirs used are in the face of the arches. A peculiar cement and hard fragmented stone has effected this with vast economy of cost and time, and promises well. The so-called Temple of Peace at Rome is ceiled and vaulted with a similar concrete. The coffering was previously moulded in all its detail upon the centreing, and then covered with grosser concrete, so that on removal of centreing all was finished. A vast fragment now lies in the middle of the Temple, and at Tivoli we find that Adrian employed the same simple process.

Sheathing Ships with Copper.

From an old pamphlet we learn that:—“Mr. Pepys, a scientific man, in the reign of Charles the Second, suggested the great importance of Sheathing Ships with Copper, and urged the advantages with sound and persuasive arguments; and says, in some despair, ‘I wish it were tried on one ship.’ But this experiment was delayed for nearly a century; and when it was tried, although it answered beyond expectation, yet the prejudice against innovation was so strong, that in Admiral Keppel’s fleet, 1778, there was only one coppered ship.”

Copper-smelting.

A prodigious quantity of copper is obtained from Lake Superior. Mr. Petherick, the well-known mining engineer, informed Dr. Percy that at Minnesota, in 1854, not fewer than forty men were engaged during twelve months in cutting up a single mass of native copper, weighing about 500 tons! The native copper at Lake Superior in some places occurs curiously intermingled, but generally not alloyed, with native silver. The following anecdote is recounted of the value of the gold in the residue from some South American copper-ores, and which was communicated to Dr. Percy by Dr. Lyon Playfair. At certain large chemical works where sulphate of copper was prepared by dissolving copper in sulphuric acid, an insoluble residue was produced in the process, which had been put aside from time to time, and had fortunately not been thrown away. A small sum was offered by certain persons for this residue, which had not previously been regarded as of much value. Suspicion was excited, especially by the quarter from which the offer proceeded, and it was declined; whereupon the residue was examined, and was found to contain 700l.-worth of gold!

Antiquity of Brass.

Dr. Percy, the able metallurgist, extracts from history the remarkable inference that the orichalcum of Cicero, and which closely resembled gold, was really Brass; this alloy of copper and zinc being the only metallic substance which it is possible to conceive the ancients could have so mistaken. The modification of brass which is termed “Muntz’s metal,” has been the subject of one of the most lucrative patents known: when its well-known proprietor died, his property was sworn under 600,000l.

Brilliancy of the Diamond.

The cause of the wonderful Brilliancy of the Diamond is not popularly known. It has no inherent luminous power; it is simply transparent, like common glass, and yet, if the latter were cut into the form of a brilliant, it could no more be mistaken for a real one than for a sapphire or an emerald. The secret, therefore, of the brilliancy of the diamond must lie in something other than its clearness or its transparency. It is owing to its great refractive power. When rays of white light pass through transparent substances they are refracted, or bent out of their former course, and under certain circumstances are separated into their constituent elements, and dispersed in the form of the well-known prismatic colours. The cut drops of glass chandeliers show a familiar example of these properties. Now, the degree in which this effect is produced by any substance depends on the refractive power it possesses, and it so happens that the diamond has this power in an extraordinarily high degree, its index of refraction being 2·47, while that of glass, or rock crystal, is only about 1·6, and of water 1·3. The effect of this great refractive capability, particularly when aided by judicious cutting, is, instead of allowing the light to pass through, to throw it about, backwards and forwards in the body of the stone, and ultimately to dart it out again in all sorts of directions, and in the most brilliant array of mingled colours; and this is the marvellous effect that meets the eye. Sir David Brewster has shown that the play of colours is enhanced by the small dispersive power of the diamond, in comparison with its refractive properties.

The general value of diamonds has been rising of late years; for, though the production is not scanty, the demand, owing to general prosperity, and the extension of ornament to wider classes in society, is largely on the increase.—Mr. Pole; Macmillan’s Magazine.

Philosophy of Gunpowder.

It may be well to have one word, as transmutation, to indicate chemical molecular change, and another, as transformation, to indicate mechanical molecular change; but, as industrialists, we must hesitate to marvel more at the one than the other. How cheerfully they labour to a common end, like twin brother and sister; the one strong by measurable strength, the other by immeasurable fascinating power, we see in the case of that great world-changer, that emblem of war, and minister of peace, Gunpowder. It needs the strong brother to fell the oaks, and with a hint from his twin to burn them into charcoal. It needs his stout arms to quarry the sulphur, and bring the saltpetre from India; to crush them into grains, and grind them together. But it also needs his weird sister, in whose palm he lays the innocent dust, to breathe upon it before the Alps are tunnelled, or Sebastopol lies in ruins.—Prof. George Wilson.

New Pear-flavouring.

The new Pear-flavouring is derived from an alcoholic solution of pure acetate of amyloxide, considerable quantities of which are manufactured by some distillers, and sold to confectioners, who employ it chiefly in making Pear-drops, which are merely barley-sugar, flavoured with this oil. There is, also, an Apple-oil, which, according to analysis, is nothing but valerianate of amyloxide.

Methylated Spirit.

Methylene is a highly volatile and inflammable liquid produced from the destructive distillation of wood; whence Methylated Spirit, or wood spirit. It is permitted to be used, duty free, in arts and manufactures. Hitherto, no effort to obtain a potable spirit from methylated alcohol has succeeded. A patent has been granted for a process which professes not only to accomplish this object, but to render wood spirit itself potable, and that, too, at a cost almost nominal; and it has afforded matter for earnest discussion among some of our leading pharmacologists, who, anxious to preserve the integrity of medicinal preparations, have not unreasonably been alarmed by the assertion that wood spirit can be so far defecated as to render it almost indistinguishable from vinous alcohol, and by the exhibition of specimens of such spirit which might be used, instead of spirits of wine, for pharmaceutical purposes. But after a series of experiments, Mr. Phillips, of the Revenue Laboratory, has not been able by the process indicated to render either methylated or wood spirit potable, although it was submitted to numerous successive distillations, which from their costliness could not be applied profitably on a commercial scale.

One of the latest Acts passed, Session 1863, was to reduce the duty on rum. It recites that by the Act 18th and 19th Victoria, cap. 38, spirit of wine was allowed to be methylated duty free; and that it is expedient to allow foreign and colonial rum to be methylated, on payment of reduced duty. Rum may now be “methylated” in the Customs’ warehouse; but the wood naphtha, or methylic alcohol, or other article to be mixed with the rum, is to be provided by the Inland Revenue Commissioners; and the mixture is to be denominated “methylated spirits,” and such spirits may be exported.

Meanwhile, the Inland Revenue returns in 1863 showed a decreased consumption of spirit, from the fact of methylated spirit taking the place of duty-paid or pure spirit. Of the one article of spirit of nitre, very little is sold which is not distilled from “methylated finish.” This increased quantity of sweet spirit of nitre sold is not taken medicinally, but is extensively used in the adulteration of potable spirits.

What is Phosphate of Lime?

Phosphate of Lime, a minute constituent of all fertile soils and of most waters, is of great value to the ivory-turner, the manure-maker, the potter, the silver-assayer, the drug-manufacturer, the dyer, and the lucifer-match maker. It reaches all of them in the shape of the bones of dead animals; dead cattle from our farms, dead horses from the Pampas of South America, dead walrusses from the Arctic icebergs, dead whales from the Pacific Ocean, dead men even from fields of battle. Land and sea-plants have, as it were, milked this essential constituent of their frames, drop by drop, from the breast of nature. Animals of all classes, from the lowest to the highest, have robbed plants of their hard-gotten gains, and made their bones strong with the precious substance. Finally, the chartered robber man has robbed them all, claiming even the relics of his brethren, and obtaining in a handful of bone dust the phosphate of tons of rock and water.—Prof. G. Wilson.

What is Wood?

Its chief ingredients, charcoal and water, are uncostly and abundant; but in themselves they are useless to the carpenter, and he cannot change them into timber. So he calls to remembrance that his great grandfather planted an acorn, which has turned its first small capital to so excellent account that now it is a timber-merchant on a large scale, and will contract with you to build a ship of war out of oak of its own making. It is with other trees as with this ancestral oak. Each, with its republic of industrious roots and leaves, is a joint-stock company with limited liability, engaging to furnish you with pine-stems for masts, fir-wood for planking, logwood for dyeing, cork-bark for bottling, oak-bark for tanning, walnut for tables, rosewood for picture-frames, satinwood for looking-glasses, willow for cradles, mahogany for wardrobes, ebony for will-chests, elm-tree for coffins.—Those trees form the Worshipful Company of Woodmakers, an ancient guild.—Ibid.

How long will Wood last?

Cedar-wood will last 1000 years. The oil of cedar-wood, mixed with oil of creosote and forced into timber by means of a pump, will be found highly preservative of all timber for shipbuilding and breakwaters. In very old buildings, the timbers where they have been whitewashed, are often found in the highest state of preservation. In olden days they cut the timber in the winter season, when the sap was most out of it; but now, for the use of tanners, it is felled in summer; the result of which is, that it shrinks, chaps, and decays, sooner than it otherwise would. The wood of the walnut-tree is very durable, and so is that of the horse-chesnut-tree. Many very ancient barns about Gravesend are built entirely of the last. In preparing wood for shipbuilding, &c., it is best to lay it in a “running stream” for a few days only, to extract the sap that remains in it, and then dry it in the sun or air, by which it neither chaps, casts, nor cleaves. The use of linseed-oil, tar, or such oleaginous matter, tends much to the preservation of wood. Hesiod prescribes “smoking” timber in order to preserve it:—

“Temonem in fumo poneres.”

Virgil advised the same method:—

“Et suspensa focis exploret Robora fumus.”

Others have advised the oil of smoke! [pyroligneous acid?] The solid stems of trees most subject to decay, are commonly found in the Irish “peat-bogs,” in such excellent preservation, that they are esteemed equal to any timber for substantial buildings; the peat being highly antiseptic and preservative. Larix (which can be procured in blocks of any size from Dantzig) is the best kind of wood for breakwaters, harbours, &c. It is capable of resisting the weather for a length of time in those situations.—Correspondent of the Builder.

The Safety Match.

The statistics of London Fires in one year (1858) show that, out of the 1114 fires forming the total of serious conflagrations, the following proportion was occasioned by the usual contrivances for procuring flame, viz.:

Children playing with lucifers12

Lucifer matches accidentally ignited7

” ” making3

” ” careless use of17

——

39

In the first of these instances the sacrifice of life and wholesale destruction of property were traced principally to the fact of children inserting lucifer matches into various nooks and crevices, where an accidental concussion had produced their ignition. The next in the series of casualties are accidents resulting from the sudden ignition of boxes or bundles of phosphorized matches. The necessity as well as the possibility of removing the fatal cause of these accidents has long been felt; and by the following contrivance such occurrences, which hitherto have led to so many terrible disasters, may be completely obviated. This invention, which has reached us from France, consists of a match which cannot ignite by friction with ordinary substances, but which bursts into flame when struck upon a chemically-prepared substance, owing to the peculiar action occurring between the two bodies which are thus brought into contact. Without the prepared strip, the matches may be struck or trodden upon without the possibility of ignition. The advantage of having these articles tipped with a material which is not inflammable per se is sufficiently obvious, not only to careful housewives, but to the owners of large establishments where the ordinary “lucifers” are now used, and, we are afraid, often left carelessly about.

The reputed inventor of the Lucifer Match died in 1859, in Stockton, aged seventy-eight. The Gateshead Observer adds to this announcement:—“In the year 1852 (August), correcting the history of ‘matches’ in the ‘Jurors’ Reports’ (Great Exhibition), we stated, says our authority, that ‘A quarter of a century ago, Mr. John Walker, of Stockton-upon-Tees, then (as now) carrying on the business of chemist and druggist in that town, was preparing some lighting mixture for his own use. By the accidental friction on the hearth of a match dipped in the mixture, a light was obtained. The hint was not thrown away. Mr. Walker commenced the sale of friction-matches: this was in April, 1827.’ Dr. Faraday, it is said, first brought the discovery into general notice.”

Pottery.—Wedgwood.

There are three conditions locally necessary to the manufacture of Earthenware: the first is the presence of coals, the second is the existence of beds of clay and the accessibility of other materials of minor importance, and the third is the requisite labour. The great Wedgwood found these conditions to be mainly fulfilled in the part of North Staffordshire now called Stoke-upon-Trent, and with an enterprise, an industry, and a perseverance which is appreciated there, set on foot a manufacture which has now become a staple, and employs, directly or indirectly, upwards of 100,000 of the population of this country, and which is at this time one of the most important articles of our commercial interchange.

Where there is coal there is generally iron, and iron works and earthenware manufactories naturally and unavoidably engender smoke; but although the inhabitants of the Potteries have refused to accept any compulsory measure, which, if recklessly carried out, might completely annihilate their trade and deprive of employment the vast number of the inhabitants of the district, yet there is no place where greater efforts have been made by private individuals voluntarily to adopt measures for the suppression of what they admit to be an evil, not in any degree to the extent set forth.

The first use of flint in pottery has been thus explained. A potter named Astbury, travelling to London, perceived something amiss with one of his horse’s eyes, when an ostler at Dunstable said he could cure him, and for that purpose put a common black flint into the fire. The potter observing it when taken out to be of a fine white, immediately conceived the idea of improving his ware by the addition of this material to the clay.

Imposing Mechanical Effects.

Mechanical force, when exerted even as a motive-power, can be employed by man on many a grand scale. The movements of massive pieces of machinery, even though moving aimlessly, still more when working for a purpose, always awaken in us the idea of power; and often also create emotions of awe and sublimity akin to those which are begotten by the spectacle of great natural phenomena. The sweep of a railway train across the country, and the dash of a war-steamer against the waves with which it measures its strength, never become paltry pageants, even though we are ignorant of the errands on which these swift coursers are bound. Still more striking are those actions of machinery which involve not only swift irresistible motion, but also transformation of the materials on which the moving force is exerted. Take, for example, a cotton-mill, which some never tire of representing as dreary and prosaic. In the basement story revolves an immense steam-engine, unresting and unhasting as a star, in its stately, orderly movements. It stretches its strong iron arms in every direction throughout the building; and into whatever chamber you enter, as you climb stair after stair, you find its million hands in motion, and its fingers, which are as skilful as they are nimble, busy at work. They pick cotton and cleanse it, card it, rove it, twist it, spin it, dye it, and weave it. They will work any pattern you select, and in as many colours as you choose; and do all with such celerity, dexterity, unexhausted energy, and skill, that you begin to see what was prefigured in the legend of Michael Scott, and his “sabbathless” demons (as Charles Lamb would have called them), to whom the most hateful of all things was rest, and ropemaking, though it were of sand, more welcome than idleness. For our own part, we gaze with untiring wonder and admiration on the steam Agathodæmons of a cotton-mill, the embodiments, all of them, of a few very simple statical and dynamical laws; and yet able, with the speed of race-horses, to transform a raw material, originally as cheap as thistle-down, into endless useful and beautiful fabrics. Michael Scott, had he lived to see them, would have dismissed his demons and broken his wand.—Prof. George Wilson.[15]

Horse-power.

In speaking of the power, or force which an engine exerts, it is necessary to have some measure of force, or standard of inference. That used in this country is a Horse-power, a force equal to that which the average strength of a horse was believed capable of exerting. This has been estimated at 33,000 lb. avoirdupois weight, raised one foot high in a minute. There have been different estimates as to the real power of horses; and it is now considered that taking the most advantageous rate, for using horse-power, the medium power of that animal is equal to 22,000 lb. raised one foot high per minute. However, the other 33,000 lb. is taken as the standard, and is what is meant when a horse-power is spoken of. In comparing the power of a steam-engine with that of horses applied to do the same work, it must be remembered that the engine horse-power is 33,000 lb. raised one foot per minute; the real horse-power only 22,000 lb.; and that the engine will work unceasingly for twenty-four hours, while the horse works at that rate only eight hours. The engine works three times as long as the horse; hence, to do the same work in a day as the engine of one horse-power, 4·5 horses would be required (33,000 × 3 = 99,000; 99,000 ÷ 22,000 = 4·5). The power of a man may be estimated at one-fifth of the real power of a horse, or 44,000 lb. raised one foot per minute.—Hugo Reid on the Steam-Engine.

The First Practical Steam-boat.

Mr. Macquorn Rankine, in supporting the opinion of Mr. Benet Woodcroft, that the title of the “first practical steamboat” is due to that vessel in which the double-acting cranked steam-engine—in short, Watt’s rotative engine—was first applied to drive the propeller,—proceeds on the principle, that to constitute a “practical” machine, that machine must be capable, not merely of working well during a series of experiments, but of continuing to work well for years, with ordinary care in its management and repairs. Such certainly never was, and never could have been the case, with any steam-boat in which the wheels were made to turn by means of chains and rachet-work—a sort of mechanism which may answer its purpose during an experiment, but which must rapidly wear itself out by shocks and rattling. Such an engine is not a “practical steam-engine;” and a vessel driven by it is not a “practical steam-boat.” Hence the importance which Mr. Rankine is disposed to ascribe to the first actual use of a permanently efficient rotative steam-engine to drive a vessel.

It may be true that as an original inventor, Symington ought to be ranked below his predecessors; because his steam-boat of 1801 was only a new combination of parts which had previously been invented separately by others—the paddle-wheel, by some unknown mechanic of remote antiquity; the application of steam to drive vessels, by a series of inventors, comprising Papin, Hulls, D. Bernouilli, Jouffroy, Miller, and Taylor; and the rotative steam-engine by Watt: still, the merit of having first used a “practical steam-engine” to drive a vessel is due to Symington.—Communicated to the Literary and Philosophical Society of Manchester, 1863.

Effect of Heavy Seas upon Large Vessels.

Professor Tennant, in considering the effect of heavy seas upon vessels of 400 to 600 feet long, remarks that the waves of the Atlantic are stated, by some captains of American “liners,” to attain an elevation of 20 feet, with a length of 160 feet, and a velocity of 25 to 30 miles per hour. Dr. Scoresby, in his paper on Atlantic waves, gives about the same mean elevation for the waves in rather a hard gale a-head; on one occasion, with a hard gale and heavy squalls, some few waves attained a height of 43 feet, with a length of nearly 600 feet, and a velocity exceeding 30 miles an hour. Other authorities assume even more than those heights and distances. The amount of strength, to resist the impact of such waves, must vary with the length and size of a ship, and the materials of which it was constructed; and as the experience of the Britannia Bridge shows, that a weight of 460 tons, at a velocity of 30 miles per hour, could be borne by a cellular tube of 460 feet span, it was demonstrated, that by the use of iron, almost any amount of strength could be given to a vessel; and as stability could be imparted by proper proportions, efficient vessels could be built of any dimensions, as has been exemplified by the Great Britain, which after remaining ashore on rocks for several months, had been got off without serious injury.

The Railway.

“Depend upon it, whenever this new mode of travelling comes into operation, we shall become altogether a faster people,” was the vaticination of a common-sense observer some thirty years since; and experience has proved the soundness of the opinion. Increased facility of moving from place to place must, more or less, affect every one except the recluse shut up in his chamber from choice, or the less fortunate one prostrated on the bed of suffering, or age—

This quickening of locomotion has multiplied our desires by adding to the means of gratifying them; a greater number of incidents and opportunities of observation is thus gained; but, being crowded into the same length of existence, the wear and tear becomes greater; the knife wears out the sheath; and men grow old before they reach mid-age; or rather, the finer portions of existence are lost, and the residue approaches a caput mortuum.

Meanwhile, the Railway is yet an incomplete invention; and it is contended that our passenger-trains are deficient in the requisite accommodation for the comfort and even health of the passengers, who are still exposed to an unnecessary vibration which, in the course of continual travelling, produces nervous diseases. Mr. Bridges Adams, the engineer, and therefore a practical authority upon the subject, maintains that the railway companies are so fettered in their operations as to be unable to make feasible improvements: were these restrictions removed, Mr. Adams contends the public would receive the advantage in many forms, in easier and cheaper transit, and in reciprocal relations of town and country, such as involve a revolution in our national economies. The same acute writer anticipates the time when our towns shall have their railway-streets, which may become a fact at no very distant future. London has already its subterranean railway; above, the air is grilled with the electric-wire railway; and the street-system is being commenced upon the banks of the Thames, and the stream is already bridged with viaducts.

Accidents on Railways.

The question of Railway Accidents involves the whole question of railway management in detail. Accidents may be called the weak points of the system, where imperfection is manifested, where failure crops out, and where the line of demarcation may be drawn between the practicable and the impracticable. “If the road is perfect,” says Captain Huish, “if the engine is perfect, if the carriages are perfect, and I will go on to say, if the signalman is perfect, and if everything about the railway is perfect, almost any amount of speed that can be got out of an engine may be done with safety. But we deal not with theoretical excellence, but with practical facts, and none of these things are perfect; and in a large machine like a railway they cannot always be kept perfect.”

Safety to life and limb is of course the most important consideration in the working of railway traffic. Yet the problem is substantially this:—There are upwards of one hundred and forty millions of passengers and seventy million tons of goods per annum conveyed over our railways; assumed that all these must be transported by railway, what is the best way to do it? It must at the best be by a species of compromise; there must be a limit to tentative measures, there must be a risk. “If you do not go at all,” says Mr. Seymour Clarke, “there is no risk of an accident; if you go one mile an hour it is more risky than if you stand still; it is a natural attendant upon all travelling, that there is a liability to accident of some sort.” And, again, Mr. Locke thinks “that where you have the certainty of inflicting an inconvenience on the public by a prospective advantage in the saving of an accident, you should be very careful how you entail perpetually recurring inconvenience for the sake of preventing an accident which may never arise.”

The Evidence adduced before the Select Committee of the House of Commons on railway accidents in 1858, from which the foregoing extracts have been made, has led the committee to the conclusion, that accidents on railways arise from three causes—inattention of servants; defective material, either in the works or the rolling stock; and excessive speed.

Of the accidents reported to the Board of Trade that happened in 1857, there appears to have been twice as many by collision between trains as by running off the rails; and of the accidents by collision, five-sixths took place between passenger-trains and goods trains; and only about one-sixth between passenger-trains one against another. It further appears that a very small proportion, not above one in twenty, of the accidents reported, have directly arisen from excessive speed, but in every case in conjunction with imperfections in the permanent way. It may be observed that the greater proportion, if not all of these accidents, may be traced primarily to the crowding of trains, timed for unequal speeds, and the want of punctuality, which involve the risk of every kind of accident as a consequence:—by a want of perfect manifestation or apprehension of signals, or by excessive speeds. As tentative measures, the free use of the electric telegraph for giving intelligence of the exact relative positions and circumstances of trains on the line, and the use of the most powerful brakes for bringing up the trains in the shortest practicable distance, are probably of the most urgent necessity. Perfect brakes are also indisputably promotive of safety in working traffic and in compensating for unavoidable irregularities. With the usual amount of braking power, a train at 50 miles per hour may not be stopped within 900 or 1200 yards. An instantaneous brake is not of course what is wanted; on the contrary, a length of 200 yards appears to be the shortest desirable space within which a train at 50 or 60 miles per hour should be stopped, so that the process of retardation should not be accompanied by risk of carriages riding over each other, or of violence to the passengers. This appears to have been accomplished by powerful systems of train-brakes. Steam-brakes applied to the locomotives and extended to the tenders, and even to the brake-vans, have been found beneficial and capable of stopping a train within half the usual distance.—Encyclopædia Britannica, 8th edit.

Railways and Invasions.

The Volunteer Review at Brighton, in 1862, afforded a good practical demonstration of the facility with which troops might be moved towards a threatened point on the particular railway which would be most likely to be required for such a duty in an actual case of emergency. On the morning of the review, 6922 Volunteers were despatched from London-bridge in 2 hours and 41 minutes, and 5170 from the Victoria Station in 2 hours and 20 minutes, without difficulty. They were conveyed in 16 trains, each composed of an engine and tender and 22 vehicles, and each carrying on an average 20 officers and 735 men; and they reached Brighton in an average of 2 hours and 28 minutes from the time of starting. The Company had also to provide for the Easter Monday traffic, and to convey upwards of 2000 Volunteers along the south coast from the several stations on their own line. Indeed, the total number of passengers who travelled upon the London, Brighton, and South Coast Railway on that day was 132,202, including Volunteers and the holders of season and return tickets.

The vast power which the railways of this country place at the disposal of the Government for the transport of troops is little known. It is in practice limited only by the number of troops that are forthcoming; and railway organization is highly favourable for the concentration of all its energies upon this object whenever it is worth while to interfere with the ordinary traffic.

Connected with the Brighton Railway system alone there are 145 locomotive engines, 1858 carriages or passenger vehicles, and 2588 waggons and trucks or merchandise vehicles, for working 240 miles: on the South-Eastern there are 179 engines, 972 carriages, and 2535 waggons, for 286 miles; and on the South-Western, 177 engines, 850 carriages, and 3488 trucks, for 444 miles. These numbers might be increased to any amount, if increase were required, at a day’s notice, by aid from the gigantic resources of the more extensive systems north of London. Excursion traffic is more difficult to manage in many respects than military traffic. A word from the commanding-officer procures an amount of order in the one case which barriers and policemen fail to do in the other. A hundred thousand men may at any time be conveyed without fatigue from London to Brighton in a single day, and they may further be transported along the coast from point to point, to Portsmouth and Weymouth on the west, and to Dover on the east, without break of gauge. They may also be brought from the north through London, and from the north, via Reading, without coming to London at all; and, indeed, the means of communication thus afforded are of so much importance to successful defence, that the railway system determines to a great extent in this country, as it has notably done in America, the strategic lines along which offensive operations must be carried on, and defensive movements effected.—Quarterly Review, No. 223.

What the English owe to naturalized Foreigners.

The industry of England owes much to the foreigners who have from time to time become settled and naturalized amongst us. Dr. Percy has stated, in his Metallurgy, that we are indebted to German miners, introduced into England by the wisdom of Elizabeth, for the early development of our mineral resources. It also appears that the Dutch were our principal instructors in civil and mechanical engineering; draining extensive marsh and fen lands along the east coast in the reign of James I., and erecting for us pumping-engines and mill-machinery of various kinds. Many of the Flemings, driven from their own country by the Duke of Alva, sought and found an asylum in England, bringing with them their skill in dyeing, cloth-working, and horticulture; while the thousands who flocked into the kingdom on the revocation of the Edict of Nantes by Louis XIV., introduced the arts of manufacturing in glass, silk, velvet, lace, and cambric, which have since become established branches of industry. The religious persecutions in Belgium and France not only banished from those countries free Protestant thought, but at the same time expelled the best industrial skill, and England eventually obtained the benefit of both.

Our mechanical proficiency, however, has been a comparatively recent growth. Like many others of our national qualities, it has come out suddenly and unexpectedly. But, though late learners, we have been so apt that we have already outstripped our teachers; and there is scarcely a branch of manufacture in which we have not come up to, if indeed we have not surpassed, the most advanced continental nations.

The invention of the steam-engine, towards the end of last century, had the effect of giving an extraordinary impetus to improvement, particularly in various branches of iron manufacture; and we began to export machines, engines, and ironwork to France, Germany, and the Low Countries, whence we had before imported them. Although this great invention was perfected by Watt, much of the preliminary investigation in connexion with the subject had been conducted by eminent French refugees: as by Desaugliers, the author of the well-known Course of Experimental Philosophy, and by Denis Papin, for some time Curator of the Royal Society, whose many ingenious applications of steam-power prove him to have been a person of great and original ability. But the most remarkable of these early inventors was unquestionably Thomas Savery—also said to have been a French refugee, though very little is known of him personally—who is entitled to the distinguished merit of having invented and constructed the first working steam-engine. All these men paved the way for Watt, who placed the copestone on the work of which the distinguished Frenchmen had in a great measure laid the foundations.

Many other men of eminence, descendants of the refugees, might be named, who have from time to time added greatly to our scientific and productive resources. Amongst names which incidentally occur to us are those of Dollond the optician; and Fourdrinier, the inventor of the paper-making machine. Passing over these, many were the emigrés who flocked over to England at the outbreak of the great French Revolution of 1789, and who maintained themselves by teaching the practice of art, and by other industrial pursuits. Of these, perhaps, the most distinguished was Marc Isambard Brunel, who for the greater part of his life followed the profession of an engineer, leaving behind him a son as illustrious as himself,—Isambard Kingdom Brunel, the engineer of the Great Western and other railways, the designer of the Great Eastern steam-ship, and the architect of many important public works.—Abridged from the Quarterly Review, No. 223.

Geological Growth.

Geologists who are familiar with the idea of Geological phenomena worked out through periods of inconceivable duration will, perhaps, be able to appreciate Mr. E. B. Hunt’s argument on the growth and chronology of the great Florida reef. After stating the dimensions of the reef, Mr. Hunt proceeds: “Taking the rate at twenty-four years to the foot, we shall have for the total time 24 × 250 × 900, on the data, as stated; or we find the total period of 5,400,000 years as that required for the growth of the entire coral limestone formation of Florida.”

“Implements in the Drift.”

We have already, at page 59, referred to these important evidences, in connexion with the mode of life of the present inhabitants of Tierra del Fuego. The geological inference must, however, be drawn with extreme caution, which induces us to return to the subject.

The period of time long before history was, for convenience we designate the “Stone Age.” We gather from manifold evidence that during this period metals were unknown. Wherever their use was introduced, there the “Stone Age” virtually ended. The recent discovery of the flint instruments of the drift seems to carry the “Stone Age” back to a period of which, till very lately, we had no idea. The interval between the time when men fashioned these thousands of implements already found in the drift, and the earliest examples of the second “Stone Age” so to speak, as the Danish “kjökkenmödding,” or the oldest Swiss “pfahlbau,” must be long indeed.

It by no means follows that all the men who have used stone weapons must necessarily have been savages. At least, a consideration of the every-day life of the Swiss “pfahlbauten” would refute such a proposition. There was progress even in the “Stone Age,” and the iron swords of the Gauls of Brennus probably differed less from the finest-tempered Damascus blade than do the flint implements of the drift from those of Denmark; or, to come nearer home, from the stone relics of our Channel Islands. There may have been an all-pervading “Stone Age,” but universality is not implied in the term. The people of the lands now Hungary and Transylvania seem to have used copper implements, preceding those of bronze, when the men of the West were fashioning their flints.

The present state of the tribes of Tierra del Fuego is their “Stone Age,” and, if ever they become a nation hereafter, they will probably collect in their museums the humble implements of their earliest culture.

The above observations were communicated to the Times, April 30, 1863: it is but a glimpse of a great subject, but is so suggestive as to be entitled to attention.

The Earth and Man compared.

If it were possible for man to construct a globe 800 feet, or twice the height of St. Paul’s Cathedral, in diameter, and to place upon any one point of its surface an atom 1/4380th of an inch in diameter, and 1/720th part of an inch in height, it would correctly denote the proportion man bears to the earth upon which he stands.

Why the Earth is presumed to be solid.

Besides the confirmation of some of the most material points of the theory of gravitation which results from the experiment of “Weighing the Earth,”[16] it furnishes a presumption of the strongest kind that the earth is solid to the centre, and not, as many have supposed in every age, a hollow shell. The mean density, 5⅔, is very much greater than that of the substances which abound at the surface. All common rocks are under 3, and nothing under the ores of the heaviest metals comes up to 5⅔. The earth is as massive as if it were all composed of silver ore, from the centre to the circumference, so that there must be an increase of density towards the centre. If those who think the earth to be a shell were to presume that its solidity ceased at 500 miles below the surface, they would then be compelled to give to the terrestrial matter, one part with another, a density greater than that of mercury, in order that the whole shell, the hollow part included, might have the mean density which is found by this experiment.—Penny Cyclopædia.

The Centre of the Earth.

Lt.-Col. Sir Henry James writes to the Athenæum as follows:—In verifying on a globe the interesting fact stated by Sir John Herschel, in his Outlines of Astronomy, and by Sir Charles Lyell, in his Principles of Geology, that the central point of the hemisphere which contains the maximum of land, falls very nearly upon London, or more exactly upon Falmouth, our most western port of departure for all parts of the habitable globe, it occurred to me to inquire what would be the central point of that portion of the globe which should include the whole of Europe, Asia, Africa, and America; and I found that the point lies in lat. 23° 3´ on northern tropical line, and in 15° E. long., near a place called Ghad in Africa, about 700 miles south of Tripoli. But the portion of the globe which, from this point as a centre, includes the so-called four quarters of the world is as near as possible two-thirds of the surface of the sphere; and I found that by projecting this portion of the sphere upon a plane drawn parallel to the great circle of which the above defined centre was in the pole and at 20° from it, and from a point in the prolongation of the axis of this great circle distant one-half of the radius from the surface of the sphere, that the whole of the four quarters of the globe could be represented on one strictly geometrical projection. I have had this projection made by Mr. J. O’Farrell, one of the highly intelligent assistants of the Ordnance Survey. I believe this is the first time that two-thirds of a sphere has been presented to the eye at one view.

The Cooling of the Earth.

It is a generally received belief among geologists, that the centre of the earth is occupied by incandescent fluid matter, which is gradually but constantly losing its heat. Adopting this theory, which rests on mere conjecture, Professor William Thomson, in a paper published in the Transactions of the Royal Society of Edinburgh, endeavours to fix the date of the first consolidation of the globe, supposed to have been once in a state of perfect liquefaction. It is estimated that the temperature increases as we descend towards the centre of the earth, at the average rate of one degree of Fahrenheit per 50 British feet, or 105 degrees per mile. Our author admits the temperature of melting rock to be 7000 degrees; supposing, therefore, the surface of the earth to have been in a fluid state, its consolidation, he thinks, cannot have taken place less than 20,000,000 years ago, since we should otherwise have more underground heat than we actually have; nor more than 400,000,000 years ago, because in that case we should have much less. This, it must be allowed, is rather a wide range, and is a curious instance of the strange results which calculation affords when applied to a gratuitous hypothesis. Compared with the earth’s radius, which is 3958 miles, the depths to which we have been able to penetrate are utterly insignificant, and can afford no reliable data whatever; the more so, as by Professor Thomson’s own admission, the rate of increase of temperature decreases progressively.

Our author, moreover, in the course of his arguments, meets with difficulties, the importance of which does not seem to have escaped him, since he endeavours to remove them by some rather doubtful assertions. To those, for instance, who would object to the supposition that any natural action could possibly produce at one instant, and maintain for ever after, a 7000 degrees’ lowering of the surface temperature of the earth, he replies:—“I answer by saying, what I think cannot be denied, that a large mass of rock exposed freely to our air and sky will, after it once becomes crusted over, present in a few hours, or a few days, or at the most a few weeks, a surface so cool that it can be walked over with impunity.” Now we do confess ourselves very much inclined to deny such a proposition. What kind of mass does our author mean? Is it a small mass? then he need but visit a gun foundry, where he will find pieces of ordnance still hot though cast several days before. Or is it a large mass, like a mountain? The nearest approach to it would be lava, which remains hot for weeks after the eruption, and for any larger mass there is no evidence either in existence or possible. But the immense difficulty of the subject may be inferred from the fact, that Professor Thomson himself further down makes an admission which is fatal to his own view, viz., that “if at any time the earth were in the condition of a thin solid shell of, suppose, 50 or 100 feet thick of granite, enclosing a continuous melted mass of 20 per cent. less specific gravity in its upper parts, where the pressure is small, this condition cannot have lasted many minutes, since the rigidity of a solid shell of superficial extent so vast in comparison with its thickness must be as nothing, and the slightest disturbance would cause some part to bend down, crack, and allow the liquid to run out over the solid.” What then, we may ask, becomes of the liquid theory altogether?—Galignani’s Messenger.