PART II. THE PRACTICE OF BREWING. (continued 2)
Reading edition
SECTION VII. OF BOILING.
It has been a question, whether boiling is necessary to a wort; but as hops are of a resinous quality, the whole of their virtues are not yielded by extraction; decoction or boiling is as needful as the plant itself, and is, together with extraction and fermentation, productive of that uniformity of taste in the compound, which constitutes good beer.
Worts are composed of oils, salts, water, and perhaps some small portion of earth, from both the malt and hops. Oils are capable of receiving a degree of heat much superior to salts, and these again surpass, in this respect, the power of water. Before a wort can be supposed to have received the whole of the fire it can admit of, such a degree of heat must arise, as will be in a proportion to the quantity of the oils, the salts, and the water. When this happens, the wort may be said to be intimately mixed, and to have but one taste. The fire, made fiercer, would not increase the heat, or more exactly blend together the constituent parts; this purpose once obtained, the boiling of the wort is completed.
It follows from thence, that some worts will boil sooner than others, receive their heat in a less time, and be saturated with less fire; but, as it is impossible, and, indeed, unnecessary, to estimate exactly the quantities of oils, salts, and water contained in each different wort, it is out of our power previously to fix, for any one, the degree of heat it is capable of. This renders the thermometer in this case useless, and obliges us to depend entirely on experiment, and to observe the signs which accompany the act of ebullition.
Fire, as before has been mentioned, when acting upon bodies, endeavours to make its way through them in right lines. A wort set to boil, makes a resistance to the effort of fire, in proportion to the different parts it is composed of. The watery particles are, it is imagined, the first, which are saturated with fire, and becoming lighter in this manner, endeavour to rise above the whole. The salts are next, and last of all the oils. From this struggle proceeds the noise heard when the wort first boils, which proves how violently it is agitated, before the different principles are blended one with another. While this vehement ebullition lasts, we may be sure that the wort is not intimately mixed, but when the fire has penetrated and united the different parts, the noise abates, the wort boils smoother, the steam, instead of clouding promiscuously as it did at first round the top of the copper, rises more upright, in consequence of the fire passing freely in direct lines through the drink, and when the fierceness of it drives any part of the drink from the body of the wort, the part so separated ascends perpendicularly. Such are the signs by which we may be satisfied the first wort, or the strongest part of the extracts, has been so affected by the fire, as to become nearly of one taste. If, at this time, it is turned out of the copper, it appears pellucid, and forms no considerable sediment.
The proper time for the boiling of a wort hitherto has been determined, without any regard to these circumstances; hence the variety of opinions on this subject; greater, perhaps, than on any other part of the process. While some brewers would confine boiling to so short a space as five minutes, there are others who believe two hours absolutely requisite. The first allege, that the strength of the wort is lost by long boiling; but this argument will not hold good against the experiment of boiling a wort in a still, and examining the collected steam, which appears little else than mere water. Those who continue boiling the first wort a long time, do it in order to be satisfied that the fire has had its due effect, and that the hops have yielded the whole of their virtue. They judge of this by the wort curdling, and depositing flakes like snow. If a quantity of this sediment is collected, it will be found to the taste both sweet and bitter, and if boiled again in water, the decoction, when cold, will ferment, and yield a vinous liquor. These flakes, therefore, contain part of the strength of the wort; they consist of the first and choicest principles of the malt and hops, and, by their subsiding, become of little or no use.
It appears, from these circumstances, that boiling a first wort too short or too long a time, is equally detrimental, that different worts require different times, and these times can only be fixed by observation.
The first wort having received, by the assistance of the fire, a sufficient proportion of bitter from the hops, is separated therefrom. The hops, being deprived of part of their virtues, are, on the other hand, enriched with some of the glutinous particles of the malt. They are afterwards, a second, and sometimes a third time, boiled with the following extractions, and thereby divested not only of what they had thus obtained, but also of the remaining part of their preservative qualities. The thinness and fluidity of these last worts render them extremely proper for this purpose. Their heat is never so intense as that of the first, when boiling; for, as they consist of fewer oils, they are incapable of receiving so great a degree of heat. This deficiency can only be made up by doubling or tripling the space of time the first wort boiled, so that what is wanted in the intenseness of heat, may be supplied from its continuance.
The following table is constructed from observations made according to the foregoing rules.
A TABLE shewing the time each wort requires to boil for the several sorts of beer, in every season.
Brown beer, keeping pale strong and keeping small beer. Small beer. amberBurtonsmall after amberkeeping small after amber
╭━━━━━━━━━━━━━^━━━━━━━━━━━━━╮ ╭━━━━━━^━━━━━━╮
Degrees of heat in the air hourshourshourshourshourshourshourshourshourshours
35°1241/2121/21/212
401241/2121/21/212
451241/2121/21/212
501241/2121/21/212
55 24 1½33/43/412
60 24 1½33/411½2
1 wort 2 wort24 3 wort1 wort 2 wort 3 wort.
It may, perhaps, be objected, that, by a long boiling of the last worts, the rough and austere parts of the hops may be extracted, and give a disagreeable taste to the liquor; but it should be observed, this only happens, either in beers to be long kept, or in such as are brewed in very hot weather. In the first case the roughness wears off by age, and grows into strength, and in the last, it is a check to the proneness musts have in such seasons to ferment.
One observation more is necessary under this head; most coppers, especially such as are made in London, and set by proper workmen, waste or steam away, by boiling, about three or four inches of the contained liquor, in each hour. The quantity wasted being found on trial, and knowing how much water the copper holds upon an inch, what is steamed away by boiling in each brewing, may easily be estimated.
SECTION VIII.
Of the Quantity of Water wasted; and of the Application of the preceding Rules to two different processes of Brewing.
Waste water, in brewing, is that part which, though employed in the process, yet does not remain in the beers or ales when made. Under this head is comprehended the water steamed away in the boiling of the worts; that which is lost by heating for the extracts; that which the utensils imbibe when dry; that which necessarily remains in the pumps and underback; and more than all, the water which is retained in the grist. The fixing to a minute exactness how much is thus expended, is both impossible and unnecessary. Every one of the articles just now mentioned varies in proportion to the grist, to the lengths made, to the construction and order of the utensils, and to the time employed in making the beer. To these different causes of the steam being lessened or increased, might be added every change in the atmosphere. However, as, upon the whole, the quantity of water lost varies from no reason so much, as from the age and dryness of the malt, experience is, in this case, our sole and surest guide. I have, in the following table, placed under every mode of brewing, how much I have found necessary to allow for these several wastes and evaporations.
Brown strong and pale strong beers.
Barrels pins.25
For old malts allow 15 per quarter.
For new26 malts 20 per quarter.
Keeping small and common small beers.
For either new or old malt allow 24 per quarter.
Amber or pale ales.
For either new or old malt allow 15 per quarter.
Keeping small or common small after amber.
Allow for waste 02 per quarter.
It is now time to begin the account of two brewings, which admit of the greatest variety, both in themselves, and in the season of the year. The same processes will be carried on, in the sequel of this work, until they be completed.27
On the tenth of July a brewing for common small beer is to be made with 6 quarters of malt.
By page 150 the medium heat of the air at this time is} 60 degrees.
By page 184 the malt to be used for this purpose should be in dryness at}130 degrees.
By page 210 the proper quantity of new hops is 6 pounds per quarter. The length, according to the excise gauge without the bills of mortality, may be rated at 5 barrels 1/8 per quarter, or from the whole grist at 30 barrels 3/4. See page 219.
By page 222, the inches required in the copper, to bring out this length, at 2 worts, will be, for coppers as gauged page 221, 56 inches in the 2 worts above brass.
The state of this part of the brewing is, therefore, six quarters of malt dried to 130 degrees, 36 pounds of hops for 30 barrels 3/4 to go out at 56 inches above brass.
30¾ Length
{Boiling by page 228
1 wort 1 hour 1/2 or 5 inches.
5¼2 wort 3 hours or 9 inches.
15 waste water page 231
——
51barrels; whole quantity of water to be used.
And by page 191 we find the heat of the first extract to be 154 degrees, and the heat of the last 174 degrees.
The other brewing, of which I purpose to lay down the process in this treatise, is one for brown beer or porter of 11 quarters of malt, to be brewed on the 20th of February.
By page 150 the medium heat of the air at this time is} 40 degrees.
By page 174 the malt to be used for this purpose should be at}130 degrees.
By page 209 the quantity of hops is 12 pounds per quarter. The length I would fix for this liquor, according to the excise gauge without the bills of mortality, is 2 barrels and 4 pins from a quarter, or from the whole grist 27 barrels 1/2. See page 219.
By page 222, the inches required, in a copper, such as I have specified page 221, to bring out this length at 3 worts, are 31 above brass.
The state of this brewing, so far as we have considered it, is therefore 11 quarters malt dried to 130 degrees, 132 pounds of hops for 27 barrels 1/2 to go out at 31 inches above brass.
27½ barrels the length,
{Boiling by page 228
1 wort 1 hour or 4 inches.
2 wort 2 hour or 6 inches.
8¼3 wort 4 hours or 12 inches.
18 waste water page 231 old
—— malt 1-5/8 per quarter.
54barrels; whole quantity of water to be used.
And by page 177 we find the heat of the first extract to be 155 degrees, and the heat of the last extract 165.
SECTION IX.
Of the Division of the Water for the respective Worts and Mashes, and of the Heat adequate to each of these.
That the whole quantity of water, as well as that of heat required, ought not, in any brewing, at once to be applied to the grist, is obvious, both from reason, and from the example of nature, who, in forming the juice of the grape, divides the process, and increasing successively both the moisture and the heat, gives time to each degree to have its complete effect. A division of the water and heat to form malt liquors is equally necessary, but previous to this division the following general rules may be laid down.
The grist, if possible, is at no time to be left with less water than what will cover the malt, to put all its parts in action. In the first mashes for strong beer, an allowance is to be made for nearly as much water as the grist will imbibe; and, lastly, the whole quantity of water used in brewing should be divided, in a proportion analogous to that of the degrees of heat.
Processes for brewing are carried on either with one copper or with two. Though the first of these methods is almost out of use, it may be necessary to give an example or two of the division of the water used in this case, the doing which will point out the absurdity of this practice.
In brewing with one copper, scarcely more than three mashes can be made; otherwise the time taken up in boiling the worts, and preparing the subsequent waters for extraction, would be so long, as to cause the grist to lose great part of its heat, and, in warm weather, perhaps, to become sour. The whole water required might naturally be divided into three equal parts, was it not for the quantity at first imbibed by the grist; but as, in this way of brewing, the best management is to make the first wort of one mash, and the second wort of the other two, it will be found necessary to allow, for the first extracting water, four parts out of seven of the whole quantity required, and to divide the remainder equally for the other two mashes. Thus, if the whole quantity of water required was fifty-one barrels, the lengths of the extracting waters would be as follow:
1 Liquor2 Liquor3 Liquor
291111 Barrels.
1 Wort.╰━━━━━━━━⌄━━━━━━━━╯
2 Wort.
The water imbibed and retained by the malt is allowed for in this computation, which will be found just to every purpose, for small beer brewed in one copper only.
But in strong beers and ales, with three mashes, whether brewed at one, two, or three worts, the case will be somewhat different, as care should always be taken to reserve for every mash a sufficient quantity of water to apply to the grist. For this reason, no greater proportion ought to be used in the first mash than that of three parts out of seven, as the volume of the malt is in a greater proportion to the quantity of water than in the preceding case. If, therefore, the whole quantity of water used was thirty-five barrels, the length of the liquors would be:
1 Liquor2 Liquor3 Liquor
151010 Barrels.
Employing only one copper, must from hence appear, and is allowed to be, bad management; for, in some part or other of the process, however well contrived, the business must stand still, and consequently the extracts be injured, by the air continually affecting them. The best and most usual practice, and that which here will be set in example, is to brew with two coppers. Other rules consequently are necessary to be observed, and I shall be more particular in the explanation of them.
To preserve order, and to convey our ideas in the clearest manner, we shall make use of the four modes of brewing we mentioned, in the fourth section.
The first of these, which implies keeping pale strong and keeping pale small beers to become spontaneously fine, are best brewed with two worts and four mashes, to allow for what is imbibed by the grist, and what is steamed away during the first part of the process, four sevenths of the whole of the water employed, and consequently a like proportion of the number of the degrees which constitute the difference between the first and last heats of the whole brewing, are required for the first wort, and the remainder to the last or second. The proportion as to the water is permanent, but having now only a division of heat in a progressive state, for the temperature to be given to the extracts, to put in practice the principles laid down in pages 64, 65; the first wort, however, composed of several mashes, must be of one uniform heat, though less than that of the second, whose extracts, though more powerful, must, notwithstanding, be of equal heat among themselves.
According to the rules laid down in section 8, the whole quantity of water requisite for a guile of keeping pale strong, or keeping pale small beer, is fifty-one barrels. In page 171, we found, including the heat lost at the time the extract separates from the grist, the first heat to form this process to be 144 degrees, and the last 158 degrees; the quantity of water, and the difference between these two degrees, are required to be divided in such proportions as are best applicable to the purpose we intend.
Water51Barrels, multiplied by
4
——
Divided by 7)204
——
Gives29Barrels for the first Wort, and this deducted from 51,
Leaves22Barrels for the second Wort.
The twenty-nine barrels, equally divided between the two first mashes, is fourteen barrels and a half for each; and the twenty-two barrels, equally divided between the two last mashes, is eleven barrels for each.
The last heat for pale keeping beers is160degrees.
And the first is146degrees.
——
Their difference is14
This, as above, multiplied by4
——
And divided by7) 56
——
Leaves8degrees.
the proportion to be allotted to the first wort, and 6 degrees, the remainder, to the last, in a regular progressive state; the elements for this brewing would stand as under.
Malt’s dryness.Value of hops.Whole medium.First mash.Second mash.Third mash.Fourth
Degrees1193138146154157160
Barrels14½14½1111
But more exactly, to imitate the fermented liquors formed by nature, our first wort, answering to the germinating part of her process must be of one uniform heat in the extracts, as must likewise our second wort: (See page 165) the mean, then, of the progressive heats of the first wort will be that which must be applied both to the first and second mashes, and the mean of the progressive heats of the second wort, that which must direct the third and fourth mashes; from whence are deduced
Elements for forming keeping pale strong and keeping pale small beers.
Malt’s dryness.Value of hops.Whole medium.First mash.Second mash.Third mash.Fourth mash.
Degrees1193138150150158½158½
Barrels 14½14½1111
╰━━⌄━━╯╰━━⌄━━╯
First wort.Second wort.
That this method of applying the heats to the mashes corresponds to the medium heat which is to govern the whole process, the circumstances required in page 165, the following operation will prove.
29Barrels, the first wort.
Heated to150
——
1450
29
——
4350
——
22Barrels, the second wort.
Heated to158½
——
11
176
110
22
——
whole3487
quantity4350
of water——
Barrels 51)7837(153The mean heat of the 4 mashes.
512Deducted for the heat lost at the tap.
————
273151Heat of the tap’s spending.
255119Malt’s dryness.
————
187270
153——
——135Mean heat of Malt’s dryness and of the extracts.
3Value of hops.
——
138Mean heat of the whole process.
——
Admitting of the necessary variations in the medium heats which are to govern processes for different purposes, and of those in the number of degrees forming the constituent parts of the must, in proportion as the drinks are to be formed, either to become spontaneously fine, or made so by precipitation, or intended for a longer or shorter duration. This rule will be found universally true, when beers are brewed with two worts: but when, for the benefit of the drink, or on account of the smallness of the utensils, as is often the case, when the second mode of extraction is put in practice, we are obliged to carry on the process with three worts, these proportions must necessarily be altered, and the following have, in this case, been found most advantageous.
The first and second wort ought to have two thirds of the water; the first wort two thirds of this quantity, the second the remainder of this, and the third wort one third part of the whole.
Porter or brown beer is the sort of drink, in which this division is most commonly observed. Let the whole quantity of water to be used be that of the brewing, of which the elements have been laid down, (page 233) or 54 barrels.
54
2
——
3) 108
——
36
2
——
3) 72
——
24Barrels of water for the first wort.
12Barrels of water for the second wort.
18Barrels of water for the third wort.
——
54
——
The last degree for this drink is, with malt dried to 130 degrees,165Degrees.
The first, as per page 178155Degrees.
——
Their difference10Degrees.
2
——
3) 20
——
7
2
——
3) 14
——
5Heat of first wort.
Five degrees to be proportioned in the first wort, and these deducted from 7 degrees, the number allowed for the first and second wort, there remains two degrees for the second wort; and seven degrees deducted from ten, the whole difference, leaves three degrees, to be proportioned in the third and last wort.
A grist of eleven quarters of malt is too large, to admit of the water allowed for the first wort to be equally divided between the first and second mash; therefore, rather than use the whole 24 barrels in one mash, a sufficient quantity only must be applied to the first mash, both to work it, and to get as much of the extract to come down, as will save the bottom of the copper it is to be pumped into. By this management, there will be enough left to form the second extract with, or what by the brewers is termed the piece liquor. The exact quantity of water the first mash should have, might be referred to the following section, but the order we have laid down, will excuse our anticipating thereon.
It has been found, and will hereafter be proved, that a volume of eleven quarters of malt, dried to 130 degrees, is equal to 6,32 barrels of liquid measure, that malt in general requires twice its volume of water to wet it, and this quantity of water is retained after every tap is spent.
6,32Barrels, volume of the 11 quarters of malt.
3
——
18,96
6,32
——
12,64Barrels of water imbibed by the grist, which, deducted from
24,00Whole quantity of water allowed for the first wort.
——
Remains3) 11,36Extract, which will be yielded from the first and second mash.
3,78Length of the first piece, which is sufficient to save the copper.
——
3,78
12,64Quantity imbibed as above.
——
16,42Quantity of water for the first mash.
7,58Quantity of water for the first mash.
——
24,00
The elements of this brewing, as we have them (page 178) placed in a progressive state, will be as under, where the quantity of water allowed for the first wort is divided into two mashes, according to the circumstances just now taken notice of, where the second wort is formed by one entire mash, and the water allotted for the third wort is separated equally into two parts, for the two last mashes, and when the ten degrees of heat, the difference between the first and last heats employed, are as near as possible proportioned to the lengths of the worts.
Malt’s dryness.Value of hops.Whole medium.First mash.Second mash.Third mash.Fourth mash.Fifth mash.
Deg.1304148155160162164165
Barrels 1681299
But, for the reasons alleged in page 236, they admit of the following variation.
Elements for brewing brown beer or porter.
Malt’s dryness.Value of hops.Whole medium.First mash.Second mash.Third mash.Fourth mash.Fifth mash.
Deg.1304148157½157½162164165
Barrels 1681299
╰━━⌄━━╯╰━⌄━╯╰━━⌄━━╯
1 wort2 wort3 wort
And, if proved as before, the same correspondence will be found with the medium governing heat.
The third mode of extraction is intended for a drink which is soon to be ready for use, in which, in the coldest season of the year, transparency is expected, and, in the hottest months, soundness: to procure these intents, we have already shewn (page 191) it was necessary to vary the medium heats governing these several processes, in proportion as the seasons of the year differed as to heat and cold. Our present business is a proper division of the whole quantity of water necessary for brewing, into the respective worts and mashes, and to apply to each, the adequate degree of heat: one single example will suffice for the operation, and the whole variety this drink is subjected to, will be expressed in the table subjoined.
The general practice to brew common small beer, and which is best, is to form it with two worts and four mashes, and, in this case, as was before practised for keeping pale beers, in order to allow for the water at first absorbed by the grist; four sevenths of the whole quantity is required for the first wort, and the remainder for the second wort, dividing these quantities again into equal parts, for their respective mashes. As a speedy spontaneous pellucidity is expected in every season of the year, and as every means for producing this without affecting the soundness of the drink, must be put in practice, the whole number of constituent parts are not only applied, but likewise the progressive heats suffered to take place: for here, through necessity, we are compelled to forsake the rules nature pointed out, (as in pages 64, 65); the reasons why are obvious; this drink receives no benefit by the slow progress nature recommends, and therefore very little by the impressions of time.
In page 232, we found the whole quantity of water to be used for the brewing there specified, fifty-one barrels, and in page 191, we find when the heat of the air is at 60, the first heat is 154, the last 174 degrees.
Water51Barrels, multiplied by
4
——
Divided by 7)204
——
Gives29for the first Wort, and this deducted from 51,
Leaves22for the second Wort.
The twenty-nine barrels, divided into the first and second mashes, will be fourteen barrels and a half for each; and the twenty-two barrels, equally divided between the third and fourth mashes, is eleven barrels each.
The last heat for this brewing of common small beer is (see page 191)74degrees.
The first heat,154degrees.
——
Their difference20
Multiplied by4
——
And divided by7) 80
——
Leaves (to avoid fractions) nearly12
to be proportioned in the first wort, and 8 degrees, the remainder of the 20, to the second wort, in a regular progressive state: the elements for this brewing are:
Malt’s dryness.Value of hops.Whole medium.First mash.Second mash.Third mash.Fourth mash.
Deg.1302148154166170174
Barrels 14½14½1111
╰━━⌄━━╯╰━━⌄━━╯
First wort.Second wort.
The quantity of water used for brewing small beer is in proportion to the largeness of the grist, and the price of the grain; this admitting of almost an endless variety, it is needless to pursue it: but the dryness of the malt, the value of the hops, the medium governing the processes, and the heat of the extracts being fixed, and constant degrees of heat in proportion to that of the air, I have constructed the following table, which will be found useful to the practitioner in every season of the year.
Heat of air.Malt’s dryness.Value of hops.Whole mash.First mash.Second mash.Third mash.Fourth mash.
351221135138150154158
401241137140152156160
451251140145157161165
501271143149161165169
551291½146152164168172
601302148154166170174
The last business of this section is to divide the quantity of water requisite to brew pale ales or amber, and to apply to such divisions their necessary degrees of heat. This liquor is rather an effort of art, than an exact imitation of nature, as in it the greatest transparency, joined to the greatest strength, is expected in a very short time. To obtain these ends, the whole number of the constituent properties of malt and two mashes only are employed. In the first, in order to favor its pellucidity, the lowest adequate extracting degree must be used; and in the second, to cause the malt to yield the whole of its necessary parts, the highest fitting heat must be applied; the whole of the process is, nevertheless, subjected to the governing medium heat of 138 degrees, the highest which admits of voluntary brightness. But where a drink is formed with two mashes only, and boiled off in one entire wort, to keep the due proportion between the quantity of water used, and the heat required in the extracts, and at the same time to allot the proper quantity for what is imbibed by the grist, the most convenient division found, will be three-fifths of the whole quantity of water to be applied to the first mash, and the remaining two-fifths to the other. I know to this, custom may be objected, that the first mash for amber should be a stiff one, in order the better to retain the heat; but this, in the division here proposed, may equally be obtained by a proper allowance made in the attemperating of the water, without affecting the proportion of the heats required, as otherwise must be the case.
From 8 quarters of malt to make 13 barrels of fine ale.
13Length.
½Boiling half hour.
12½Waste water.
——
26Whole water employed, multiplied by
3
——
Divided by5) 78
——
Gives16Barrels for the first mash, and leaves
10Barrels for the second mash,
the lowest heat being required in the first extract, and the highest in the last, according to page 194; for the 16 barrels it will be 144, and for the 10 barrels it will contain 164 degrees.
But as the heat of the air occasions a difference in the quantities of hops to be used, and as from hence the extracts are somewhat varied: it has been judged convenient to add the following table:
A TABLE of the elements for forming pale ale or amber, at every degree of heat in the air, with the allowance of two degrees of heat, in the first and last extractions.
Heat of airMalt’s drynessValue of hops.Medium heat of the extracts, and of malt’s dryness.First heat.Last heat.
35120½138147167
40120¾138146167
451201138146166
501201½138145165
551201½138145165
601202138144164
In summer time, it is sometimes thought better to brew this drink with malts more dried; for conveniency sake, I here insert two examples.
Heat of air.Malt’s dryness.Value of hops.Whole Medium.Heat of first mash.Heat of last mash.
601222138142162
601242138140160
For the management of small beer made after amber, see page 197.
Thus having shewn how to ascertain the quantities of the malt, the hops, the water, and the heat to be used, and to proportion them to each other, as the good or bad properties of beers arise from the extracts, and fire is the governing agent, we must now seek the means to administer the right portion of heat, and so to temper the water that is to form the extracts, as not to be disappointed of our intentions. In the calculations made for this purpose, not only the water in the copper, but the value and effect of the grist, as to heat and cold, must be considered.
SECTION X.
An enquiry into the Volume of Malt, in order to reduce the Grist to liquid Measure.
The gallon, by which malt is measured, though less, is nearly of the same capacity with that, which is used for beer or water. The quarter of malt, contains 64 gallons of this measure, and the barrel, within the bills of mortality, according to the gauges used by the excise, contains 36 gallons, but without the bills, 34; though the first quantity is the measure for sale throughout the kingdom. Hence it would appear, that proportioning the grain to the barrel of water would be no difficult undertaking. This however is so far from being the case, that, after having made use of several calculations to help us to the true proportions, we shall find, they want the corroborating proofs of actual experience, to be entirely depended upon.
The ultimate parts of water are so very small, as to make this, as well as all other liquids, appear to the eye one continued uniform body, without any interstices. This cannot be said of malt laying together either whole or ground; there are numbers of vacancies between the corns, when whole, and between the particles when ground, but for our present purpose the volume occupied by any quantity of malt is properly no more, than the space which would be occupied by every individual corn, either whole or cut asunder, were they as closely joined together as water.
To determine, with precision, the quantity of cold water to be added to that, which is brought to the boiling point, (an act by the brewers called cooling in) it is necessary to know, what proportion a quarter of malt bears to the measure of a barrel of water. Several operations will be found requisite to come to this knowledge; viz. to take several gauges of different brewings, more especially in the first part of the process; to be well acquainted with the degree of dryness of the malt used, the heat of the first extract, and the quantity of liquor the mash tun holds upon every inch; to find out what degrees of expansion are produced by the different degrees of heat in the first mash, how much less water the mash tun holds upon an inch when hot, than it does when cold, what quantity of water is lost by evaporation, and in what proportion at the several terms of the process. In order to put this in practice, the gauges of the following brewings were taken.
5 quarters of malt dried to 125 degrees.
B28. F. G.
The quantity of water used for the first mash was set}12 2 3
The malt and water gauged together in the mash tun just before the tap was set} 25, 00 inches.
Allowance for the space under the false bottom boards of the mash tun, as near as could be computed} 0, 66 inches.
The goods gauged in the mash tun, after the first tap was spent}15, 41 inches.
B. F. G.
First piece gauged in the copper 8 0 2
———————————
B. F. G.
The water employed for the second mash was}12 2 3
The grist gauged with this water just before the tap was set}30, 62 inches.
And just after the tap was spent 15, 63 inches.
B. F. G.
The first wort consisting of these two pieces gauged in the copper}21 2 0
———————————
B. F. G.
The water used for the third mash was 8 3 6
Just before the tap was set the grist with this gauged in the mash tun}24, 60 inches
And just after the tap was spent 15, 20 inches.
———————————
B. F. G.
The water used for the fourth mash was 8 3 6
The mash gauged just before the tap was set}24, 60 inches.
And just after the tap was spent 15, 16 inches.
The heat of the first extract was 136 degrees, to which adding two degrees, for what is lost by the tap spending, the true heat of the mash is 138 degrees.
The first extract, before it is blended with hops, may be estimated to be nearly as strong as a first wort of common small beer. This, when under a strong ebullition, raised the thermometer to 216 degrees, and seven barrels of such a wort, when boiling, occupied an equal space with nine barrels of cold water, at the mean temperature of 60 degrees. Now, if the degrees of expansion follow the proportion of those of heat, the following table, constructed upon this supposition, will shew how many barrels of cold water would be necessary to occupy the same space with seven barrels of wort of different heats.
Degrees of heat.Barrels of cold water.Barrels of wort.
2169,007
2068,877
1968,757
1868,627
1778,507
1678,377
1588,257
1488,127
1388,007
1277,877
1197,757
The quantity of water evaporated in a brewing, when not in immediate contact with fire, is more considerable than it is generally apprehended to be; after repeated trials, I have found that what was lost in this manner amounted nearly to one fifth.
Now since the heat of the first tap was 138 degrees, and my mash tun holds 20,25 gallons upon an inch, the following proportion may be deduced from the preceding table.
If 8———————7———————— 20,25
————
8,00) 141,7500
————
17,71Gallons,
and this is the true quantity contained in one inch, at a heat of 138 degrees.
The quantity of water used for the first mash, was 12B. 2F. 3G. or 428 gallons, of which one fifth is supposed to be steamed away, when the first liquor is gone through the whole process of the extraction: but as the gauges of the malt and water together are taken before the tap is set, in the beginning of the process, the whole evaporation ought not to be deduced, and one sixth seems to be a sufficient allowance on this account. We may therefore suppose 357 gallons to be in the mash tun at the time of gauging, which number being divided by 17,71, will shew how many inches are taken up by the water at that heat.
17,71)357,0000(20,15 3542 ——— 2800 1771 ——— 10290 8855 ——— 1435
The mash gauged just before the tap was set,25,00 Inches.
Allowed for the space under false bottoms,0,66
——
25,66
Deduct the inches taken up by the water,20,15
——
Remainder for the five quarters of malt,5,51 Inches.
or 1,10 inch for one quarter. This number being multiplied by 17,71, the quantity of gallons contained upon one inch at this heat, will give 19,48 gallons for the volume of one quarter of this malt. There now remains nothing but to bring a barrel of water of 34 gallons, under like circumstances, as to expansion and evaporation, with these 19,48 gallons, with this difference only, that as the proportion required is, at the time the water and malt first come in contact, and not after the mash has been worked, a less allowance for steaming will be sufficient, and may well be fixed at one seventh.
Gauge within the bills of mortality.Gauge without the bills of mortality.
If 7,00 8,00 36If 7,00 8,00 34
36 34
—— ——
4800 3200
2400 2400
—— ——
7,00)288,00 7,00)272,00
—— ——
41,14 38,85
5,87Lost by steam.5,55Lost by steam.
—— ——
35,24 33,30
The barrel of water reduced; and as 19,48 gallons, under the same circumstances, were found equal to one quarter of malt, the following division will shew the proportion, between them.
19,48)35,2400(1 8119,48)33,3000(1,70
1948 1948
——— ———
15700 13820
15584 13636
——— ———
1760 184
1948
———
Thus, in malt dried to 125 degrees, the quantity of 1,70 quarters is required to make a volume equal to 34 gallons, or a barrel of water, according to the excise gauging without the bills of mortality; and the quantity of 1,81 quarters is required to make a volume equal to 36 gallons, or a barrel of water, according to the excise gauging within the bills of mortality.
The more the malt has been dried, the larger the interstices are between its parts; the quantity of water it admits will consequently be greater than what is absorbed by such as is less dry. More of this last malt will be necessary to make a volume, equal to that of the barrel of water; and every different degree of dryness must cause a variety in this respect. It will therefore be proper to repeat the operation with a high-dried grist.
Gauges of a brewing of eight quarters of malt dried to 140 degrees.
B. F. G.
The quantity of water used for the first mash,}11 2 4
The malt and water gauged together in the mash tun just before the tap was set,} 26,25 Inches.
Allowed for the space under the false bottom of the mash tun,} 0, 66 Inches.
Goods gauged in the mash tun after the first tap was spent,} 22,36 Inches
B. F. G.
First piece gauged in the copper, 5 0 0
———————————
B. F. G.
The water for the second mash was 11 2 4
The mash gauged just before the tap was set, 35,70 Inches.
Just after the tap was spent, 22,19 Inches.
B. F. G.
The wort made of these two pieces gauged in the copper,} 17 0 0
———————————
B. F. G.
The water used for the third mash was 8 3 6
The mash gauged just before the tap was set 31,10 Inches.
And just after the tap was spent, 21,77 Inches.
———————————
B. F. G.
The water used for the fourth mash was 8 3 6
The mash gauged just before the tap was set 30,50 Inches.
And just after the tap was spent 21,60 Inches.
The heat of the first extract was 142 degrees. Now, by the table of expansions (page 256).
G.
If 8,05 7,020,25of cold water, upon
700an inch in mash tun.
———
8,05)1417500(17,60 will be the real
805quantity of water.
———upon an inch in the
6125mash tun, when heated
5635to 142 degrees.
———
4900
4830
———
700
B.F. G.
Quantity of water in the first mash,112 4
34
——
44
33
17
4
——
395
Deduction for the evaporation at this period, one sixth,65,83
——
329,17true quantity
of the water for the first mash, which must be divided by the real quantity of water contained upon an inch in the mash tun.
17,60)329,1700 (18,70 inches taken up in the mash tun, by the water used in the first mash.
1760
———
15317
14080
———
12370
12320
———
50
The mash gauged just before the tap was set26,25Inches.
Allowed for the space under the false bottoms0,66
——
26,91
Inches taken up by the water of the first mash18,70
——
Space occupied by these 8 quarters of malt8) 8,21Inches of
——mash tun.
Space occupied by one quarter1,02
17,60
——
6120
714
102
——
17,9520Gallons of
water equal in volume to one quarter of this malt.
Excise gauge without the bills of mortality.
If 7,008,0534
34
——
3220
2415
——
7,00)273,70
——
39,10Expansion of the barrel of
water out of which 1/7th,5,58is to be deducted for
evaporation.——
Remains,33,52for the barrel of water
reduced, which the quarter of malt, or 17,95, is to be compared to.
Excise gauge within the bills of mortality.
If 7,08,0536
36
——
4830
2415
——
7,00)289,80(41,44 Expansion of one barrel of water,
2800
——592 1/7th to be deducted for evaporation.
980——
70035,52 Barrel of water reduced, which the quarter of malt, or 17,95 is to be compared to.
——
2800
2800
——
17,95)33,5200(1,86Quantity of malt dried to 140 degrees equal to one barrel of water.
1795
——
15570
14360
——
12100
10770
——
1330
17,95)35,3700(1,97Quantity of malt dried to 140 degrees, equal to one barrel of water, according to the excise gauge within the bills of mortality.
1795
——
17420
——
12650
12565
——
Having found the volume of malt at two distant terms of dryness, we might divide the intermediate degrees in the same manner as we have done before, could the certainty of these calculations be entirely depended upon; but as some allowances have been made without immediate proof, how near soever truth the result thereof may from experiments appear, it may be proper to point out what is wanting to make our suppositions satisfactory.
Some part of the calculation depends on the quantity evaporated; this, in the same space of time, may be more or less, as the fire under the water is brisk or slow, or as the weight of the atmosphere differs. The gauges are taken at the time the malt and water are in contact, and more or less water may be imbibed in proportion, both of the dryness and age of the malt; water as a fluid, malt as a porous solid body, must differ in their expansion, but in what proportion is to me unknown; effervescence may be another cause of want of exactness; the different cut the malt has had in the mill, its being or not being truly prepared, and lastly the difference as to time, of the mashing or standing of the grist, prevent our relying wholly upon the calculation. It is, however, not improbable that some of these incidents correct one another. Since 1,70 quarter of malt dried to 125 degrees are equal to one barrel of water, and 1,86 quarter of malt dried to 140 have the same volume, the difference being but 16 parts out of 100, the whole of the error cannot be very great, and one quarter six bushels of malt may, at a medium, be estimated of the same volume with one barrel of water. But, as experience is the surest guide, I have, from a very great number of different brewings, collected the following proportions, and repeatedly found them to be true. I have added, in the table, the weight malt ought to have, at every degree of dryness.
A TABLE shewing the quantity of malt of every degree of dryness, equal to the volume of one barrel of water, and of the mean weight of one quarter in proportion to its dryness.
Degree of dryness. Excise gauge without the bills. Volume of grain. Excise gauge within the bills. Volume of grain. Weight in pounds
Barley801,561,59376
1001,621,63306
1051,621,67301
1101,651,71296
1151,671,75291
Malt1191,681,79286
1241,711,83281
1291,741,87276
1341,771,91271
1381,801,95266
1431,832,00261
1481,862,03256
1521,892,07251
1571,922,11246
1621,952,15241
1671,982,19236
1712,012,23231
1762,042,27226
With a table thus constructed, it is very easy to reduce every grist to its proper volume of water. Suppose those of the brewings we have already mentioned; that of the small beer consists of 6 quarters of malt dried to 130 degrees, the proportion of which in the table is as 1,75 to 1.
Quarter of malt.Barrel of water.Malt.Water.
If 1,75 163,42.
These six quarters of malt occupy therefore an equal volume with 3,42 barrels of water. A brown beer grist of 11 quarters dried to 130 degrees; the proportion of this in the table is as 1,74 to 1.
Malt.Water. Malt.Water.
If 1,74 1116,32
The volume of these 11 quarters of malt is therefore the same with that of 6,32 barrels of water, and the whole being brought to one denomination, we are enabled to find the heat of the first mash; but the effervescence occasioned by the union of the malt and water must prevent this calculation being strictly true, the consideration of which shall take place hereafter.
The circumstances are different in the other mashes: the waters used for these, meet a grist already saturated, and the volume is increased beyond the quantity found for dry malt. The quantity to be allowed for this increase cannot be determined by our former calculations, and new trials are to be made, in order to fix upon the true proportion.
Gauging is undoubtedly the most certain method of proceeding in these researches; but even this becomes less sure, on account of the expansion, evaporation, effervescence, and other incidents already mentioned.—Our errors however cannot be very considerable, when we deduce our conclusions from numerous and sufficiently varied experiments.
The volume of the grist of pale malt was found, after the parting of the first extract, to be 15,41 inches, though the space occupied by the malt, when dry, was only 5,51 inches: and the volume of the brown grist, at the same period, was 22,36 inches, though the dry malt filled only a space of 8,21 inches. The proportion in both these cases, and in all those which I have tried, answers nearly to one third, so that the volume of the grist, in the second and all subsequent mashes, may be estimated at three times the bulk of the malt when dry, and this is sufficiently accurate for the operations of brewing, in which, for conveniency sake, the application of whole numbers should be effected.
As it is found, by the gauges, that the goods, after the several taps are spent, remain sensibly of the same volume, or at least very little diminished; may we not conclude, the parts absorbed by the water, in which the virtue of the grain and the strength of the beer consist, are contained in an amazing small compass? It is indeed true that hot waters and repeated mashes do swell somewhat the hulls and skins of the malt, but no allowance made for this increase will be sufficient, to remove the cause of our surprise.
SECTION XI.
Of the Proportion of cold Water to be added to that which is on the point of Boiling, in Order to obtain the desired heat in the Extract.
The degree of heat, which causes water to boil is determined, by Farenheit’s scale, to 212. It is in our power to give to any part of the extracting water this degree of heat; and by adding to it a sufficient proportion of water of an equal heat with that of the air, and blending these two quantities with the grist, to bring the whole to the required temperature. The rules for obtaining this end are extremely simple, and cannot be unknown to those, who are skilled in arithmetical operations. But as our view is to render this part of our work generally useful, we think it will be proper briefly to lay down these rules, and to illustrate them by the examples of our two brewings.
Rule to ascertain the heat of the first Mash.
Let a express the degree of boiling water, b the actual heat of the air, c the required degree for the extract, m the whole quantity of water to be used, n the volume of the malt; x, that part of the water, which is to be made to boil, will be determined by the following equation.
——— ———
c - b×m + n
x =—————————
a - b
The quantity of water used, added (+) to the volume of the grist.
Their sum (z) multiplied (×) by the heat required, less (-) the heat of the air.
This produce divided (÷) by the heat of boiling water (212) less (-) the heat of the air will quote how much is to be made to boil or brought through (212) that is how high the copper is to be charged, the remainder of the length of the whole liquor for this mash, is the quantity to be cooled in.
The first example is that of a brewing of small beer, when the heat of the air is at 60, (see page 232.) The volume of the 6 quarters of malt was estimated at 3,42 barrels, (see page 268;) the first liquor is 14½ barrels, (see page 247) and the heat required for the first mash 154 degrees, (see page 247.)
First Mash.
m = 14,50Barrels of water
n =3,42Volume of grist
——
m + n = 17,92c = 154 Heat of the first mash,
94b = 60 Heat of the air,
————
(a) heat of c - b = 94
boiling water, 2127168
b heat of the air, 6016128
————
a - b = 152)168448(1108 barrels of water, to be made to boil out of the 14 + 1/2 barrels which are allotted for the first mash. The incidents to be mentioned, are not considered in this calculation.
152
——
164
152
——
1248
1216
——
The next example of a brewing is that of a grist of eleven quarters of malt for porter or brown beer; the medium heat of the air is forty degrees, the volume of the grist, 6,32 barrels, (see page 268) the first liquor to mash with sixteen barrels, (see page 245) and the heat expected in the mash, one hundred and fifty-seven and a half29 degrees. (See page 245).
First Mash of brown strong beer.
16,00Barrels of water
6,32Volume of malt
—— 157 Heat required in the
22,32 mash, vide page 247.
117 40 Heat of the air.
————
Heat of boiling15624117
water, 2122232 ——
Heat of air, 402232
————
172)261144(15,18 barrels of water, to be
172 made to boil out of the
—— 16 barrels.
891
860
——
314
1324
——
I will give one proof of the certainty of this rule, by setting down the state of this first mash from it.
15,18
212
———
3036
1518
3036
———
A.3218,16Number of degrees of heat in 14,66 barrels of boiling water.
16,00Barrels of water to first mash.
15,18Barrels made to boil.
———
,82Barrel to cool in.
40Heat of cold water.
40Heat of cold water.
B.32,80Number of degrees of heat in 1,34 barrels of cold water.
15,18Boiling water.
,82Cold water.
6,32Volume of grist.
———
C.22,32Barrels, volume of the whole mash.
6,32Barrels, volume of the 11 quarters of malt.
,40Heat of the grist.
———
252,80Number of degrees of heat in the grist.
32,80B.
3218,16A.
———
C.22,32 )350376(157 degrees of heat required in thefirst mash, as above.
2232
———
12717
11160
———
15576
15624
———
So long as the mixture consists only of two quantities of different heat, as is always the case of the first mash, the preceding solution takes place. But in the second and other mashes, where three bodies are concerned, each of different heat, viz. the boiling water, the cold water, and the mash, are to be mixed, and brought to a determinate degree, the rule must be different; yet, like the former, it is the same with what is used in similar cases of allaying, when different metals are to be melted down into a compound of a certain standard, or different ingredients of different value to be blended, in order to make a mixture of a determinate price. What the different density of the metals, or the different value of the ingredients are, in these cases, the different degrees of heat of the boiling water, the grist, and the air, are in this.
Rule to ascertain the heat of the second mash, and of the subsequent ones.
Let the same letters stand for the things they signified before, and d express the actual heat of the grist, then will
—— ——
x =c — b × m +c — d × n
——————————
a — b
or in plain terms, the heat required less (-) the heat of the air, multiplied (×) by the quantity of water used.
The heat required less (-) the heat of the goods, multiplied (×) by the volume of the goods.
Their sum (z) divided (÷) by the heat of boiling water, (212) less (-) the heat of the air.
Will quote the quantity to be made to boil, or to be brought through (212) the remainder part of the whole liquor for the mash is consequently the quantity to be cooled in.
We may now collect the circumstances of the two brewings, and find the quantity of boiling water, required for their second and subsequent mashes, exclusively of the incidents which will hereafter be mentioned.
The first mash for the six quarters of small beer, had 154 degrees of heat, but this and every mash loses, in the time the extract is parting from it, 4 degrees, which reduces the heat to 150 degrees. The volume of this grist, in its dry state, was 3,42 barrels, but now, by being expanded, and having imbibed much water, it occupies three times that space, or 10,26 barrels; the air is supposed to continue in the same state of 60 degrees of heat. The length and heat to be given to the three remaining mashes, are as follows. (See page 247.)
Degrees of heat,154166170174
Barrels of water,14½14½1111
Liquors,1st2d3d4th
╰━━⌄━━╯╰━━⌄━━╯
1 wort.2 wort.
Second Mash for Small Beer.
c = 166Heat required in the mash.
d = 150Heat of the goods.
——
c - d = 16
n = 1026Volume of the goods.
——
96
32
160
——
c - d × n =16416
c = 166Heat required in the mash.
b = 60Heat of the air.
——
c - b = 106
m = 1450Barrels of water.
——
5300
424
106
——
c - b × m = 153700
c - d × n = 16416
——
a - b = 152)170116(11,19 Barrels of water to be made to
152boil out of the quantity allotted
a = 212——for the second mash.
b = 60 181
——152
152——
291
152
——
1396
1368
Third Mash.
170Heat of mash.170Heat of 3rd mash.
60Heat of air.162Heat of goods.
—— ——
110 8
1100Barrels of water1026Volume of grist.
——3d mash.——
11000 8208
110
——
121000
8208
——
152)129208(8,50 Barrels to be made to boil out of the quantity of water allowed for the third mash.
1216
——
760
760
——
8
Fourth Mash.
174Heat of 4th mash.174Heat of 4th mash.
60Heat of air.166Heat of goods.
—— ——
114 8
11,00Barrels of water1026Volume of goods.
——for 4th mash.——
11400 48
114 16
—— 80
125400 ——
8208 8208
——
152)133608(879 Barrels to be made to boil out of the quantity of water allowed for the fourth mash.
1216
——
1200
1064
——
1368
1368
——
The liquors of this brewing of common small beer, when the mean heat of the air is 60 degrees, must therefore be ordered in the following manner (the incidents hereafter to be noticed, excepted.)
1 Liqr.2 Liqr.3 Liqr.4 Liqr.
Lengths of liquors,14½14½1111
————————
Boiling water; barrels,1111½8½8¾
Cold water; barrels,3½3¼2½2¼
————————
14½14¼1111
————————
The heat of the first mash for the 11 quarters of brown beer, was 157 degrees, (see page 245) and after the parting of the extract from it, 153; the volume of the grist, in its dry state, was valued at 6,32 barrels of water, (see page 268) but, for the reasons before mentioned, it now occupies three times that space, or 18,96 barrels. The air is supposed to continue at 40 degrees, and the length and heat to be given to the different mashes, were determined as follows: (see page 245.)
Degree of heat,157158162164165
Barrels of water,1681299
Liquors;1st 2d 3d 4th 5th
╰━━━⌄━━━╯╰━⌄━╯╰━━━⌄━━━╯
1 wort.2 wort.3 wort.
Second Mash of Porter, or brown strong.
212Boiling water.
40Heat of air.
——
72
158Heat of 2nd mash.
158Heat of the grist or goods.
——
5
1896Volume of goods.
——
158Heat of 2nd mash30
40Heat of air45
—— 40
118 5
8,00Barrels of——
——water.9480
94400 ——
9480
——
172)103880(6,03 Barrels of water to be made to boil for the second mash.
1032
——
680
516
——
Third Mash.
212Heat of boiling water.
40Heat of air.
——Heat of air.
172
162Heat of 3rd mash.
154Heat of goods.
——
162Heat of 3rd mash.8
40Heat of air.18,96
—— ——
122 48
12,00Bar. of water.72
—— 64
146400 8
15168 ——
—— 15168
172)161568(9,45 Barrels of water to be made to boil for third mash.
1548
——
776
688
——
888
860
——
Fourth Mash.
164Heat of 4th mash.
158Heat of goods.
——
6
18,96Volume of grist wetted.
164Heat of 4th mash.——
40Heat of air.36
—— 54
124 48
9,00Bars. of water.6
—— ——
111600 11376
11376 ——
——
172)122976(7,14 Barrels of water to be made to boil for the fourth mash.
1204
——
257
172
——
856
688
——
168
Fifth Mash.
165Heat of 5th mash.
160Heat of Goods.
——
5
18,96
165Heat of 5th mash.——
40Heat of air.30
—— 45
125 40
9,00Barrels of water.5
—— ——
114500 9480
9480
——
172)123980(7,20 Barrels of water to be made to boil for the 5th mash.
1204
——
358
344
——
140
The liquors of this brewing of brown beer must therefore be ordered in the following manner:
Barrels of boiling water,15¼69½77
Barrels of cold water,¾22½22
——————————
1681299
Liquors,1st.2nd.3rd.4th.5th.
What in the brewery is generally called cooling in, must be settled for this brewing according to the number of barrels of cold water specified as above, the incidents hereafter to be noticed excepted.
Each of these calculations may be proved in the same manner as was done before. This method of discovering the proportion of water to be cooled in, deserves, on account of its plainness and utility, to be preferred to any other, which depend only upon the uncertain determination of our senses.
SECTION XII. OF MASHING.
Of late years, great progress has been made towards perfecting the construction and disposition of brew-house utensils, which seem to admit of very little farther improvement. The great copper, in which the waters for two of the extracts receive their temperature, is built very near the mash tun, so that the liquid may readily be conveyed to the ground malt, without losing any considerable heat. A cock is placed at the bottom of the copper, which being opened, lets the water have its course, through a trunk, to the real bottom of the mash tun. It soon fills the vacant space, forces itself a passage through many holes made in a false bottom, which supports the grist, and, as the water increases in quantity, it buoys up the whole body of the corn.
In order to blend together the water and the malt, rakes are first employed. By their horizontal motion, less violent than that of mashing, the finest parts of the flower are wetted, and prevented from being scattered about, or lost in the air.
But as a more intimate penetration and mixture are necessary, oars are afterwards made use of. They move nearly perpendicularly, and by their beating, or mashing, the grains of the malt are bruised, and a thorough imbibition of the water procured.
The time employed in this operation cannot be settled with an absolute precision. It ought to be continued, till the malt is sufficiently incorporated with the water, but not so long as till the heat necessary to the grist be lessened. As bodies cool more or less speedily, in proportion to their volume, and the cohesion of their parts, a mash which has but little water, commonly called a stiff mash, requires a longer mashing to be sufficiently divided, and, from its tenacity, is less liable to lose its heat. This accounts for the general rule, that the first mash ought always to be the longest.
After mashing, the malt and water are suffered to stand together unmoved, generally for a space of time equal to that they were mashed in. Was the extract drawn from the grain as soon as the mashing is over, many of the particles of the malt would be brought away undissolved, and the liquor be turbid, though not rich. But, by leaving it some time in contact with the grain, without any external motion, many advantages are gained. The different parts of the extract acquire an uniform heat, the heaviest and most terrestrial subside, the pores being opened, by heat, imbibe more readily the water, and give way to the attenuation and dissolution of the oils. When the tap comes to be set, or the extract to be drawn from the grist, as the bottom of the mash is become more compact, the liquor is a longer time in its passage through it, is in a manner strained, and consequently extracts more strength from the malt, and becomes more homogeneous and transparent.
Such are the reasons why the grist should not only be mashed pretty long, but likewise be suffered to rest an equal time. It is the practice of most brewers, and experience shews it is best, to rake the first mash half an hour, to mash it one hour more, and to suffer it to stand one hour and a half. The next extract is commonly mashed three quarters of an hour, and stands the same space of time; the third, and all that follow, are allowed one half hour each, both for mashing and standing.
The heat of the grist being in this manner equally spread, and the infusion, having received all the strength from the malt, which such a heat could give it, after every mashing and standing, is let out of the tun. This, undoubtedly, is the fittest time to observe whether our expectations have been answered. The thermometer is the only instrument proper for this purpose, and ought to be placed, or held, where the tap is set, adjoining to the mouth of the underback cock. The observation is best made, when the extract has run nearly half; and as, by it, we are to judge with what success the process is carried on, it is necessary to examine every incident, which may cause a deviation from the calculated heat.
SECTION XIII.
Of the Incidents, which cause the Heat of the Extract to vary from the Calculation, the allowances they require, and the means to obviate their effects.
By incidents, I understand such causes as effect either the malt, the water, or the mash, during the time the brewing is carrying on, so as to occasion their heat to differ from what is determined by calculation. As these might frequently be a reason of disappointment, an inquiry into their number and effects will not only furnish means to prevent and rectify the errors they occasion, but also serve to confirm this practice.
In our researches on the volume of malt, some notice was taken of the increase of bodies by heat, and the loss occasioned by evaporation. Water, when on the point of ebullition, occupies the largest space it is susceptible of; but contracting again, when cold water is added to it, the true volume of both, when mixed together, remains uncertain, and may cause a difference between the calculated and real degree of heat. This cause, however, producing an effect opposite to, and balanced in part by evaporation, becomes so inconsiderable, as hardly to deserve any farther consideration.
Water, just on the point of ebullition, may be esteemed heated to 212 degrees. Though, by the continuation of the fire, or by any other cause30, the heat never goes beyond this, yet was cold water added to that, which violently boils, the degree expected from the mixture would be exceeded; for the cold water absorbing the superfluous quantity of fire, which otherwise flies off, becomes hot itself, and frustrates the intent. The time, therefore, of adding the cold water to the hot is immediately before the ebullition begins, or when it is just ended; and in proportion as we deviate from this practice, the heat in the extract will differ from the calculated degree.
The water, for every mash, should, as near as possible, be got ready to boil, and be cooled in just before it is to be used. A liquor, which remains a long time after the ebullition is over, and the fire has been damped up, loses part of its heat, if cold water is applied to it, the effect cannot be the same as it would have been at first. On the contrary, if the liquor is got ready too soon, and cold water immediately added to it, in order to gain the proper degree of temperature, by leaving the mixture long together, though the fire is stopped up, more heat than necessary will be received from the copper and brickwork, especially if the utensils are large. In both cases, the degree in the extract will not answer the intent.
The effect of effervescence next deserves our consideration, but this takes place only when the water first comes in contact with the malt. Germinated grains must, to become malt, be dried so, that their particles are made to recede from one another, thus deprived of the parts, to which their union was due, when they come in contact with other bodies, (as water) they strongly attract the unitive particles they want, and excite an intestine motion, which generates heat. This motion and this heat are more active in proportion as the grain has more strongly been impressed by fire, and the extracting water is hotter.
A large quantity of liquor applied to the grist is less heated than a small one, by the power of effervescence. The least quantity of water, necessary to shew that power, must be just so much as the malt requires to be saturated, which we have seen to be double the volume of the grain. When more water than this is applied to the grist, the real effervescing heat is by so much lessened, being dispersed in more than a sufficient space.
A table shewing the heat of effervescence for every degree of dryness in the malt, can only be formed from observations. To apply this table to practice, and to find out, for any quantity of water used in the first mash, the degrees of heat produced by effervescence, three times the volume of the grist must be multiplied by the number expressing the effervescing heat for malt of such a degree of dryness, and this produce be divided by the real volume of the whole mash.
A TABLE shewing the heat occasioned by the effervescing of malt, for its several degrees of dryness.
Dryness of malt.Heat of effervescence.
119°0
1243½
1297
13410½
13814
14317½
14821
15224½
15728
16231
16735
17138½
17640
Malt dried only to 119 degrees, raises no effervescence, and the strongest is generated by malt dried to 176 degrees; the heat produced by this amounts to 40 degrees, but the number of effervescing degrees, in this or any other case, are reached but from success attending our endeavours, ultimately to penetrate the malt by heated water, or not until the grist is perfectly saturated, which, in point of time, generally takes up the whole space of the first mashing and standing; the air, therefore, cannot cause any diminution of heat, an incident which affects considerably every subsequent mash.
The little copper being more distant from the mash tun than the other, the water there prepared, in its passage to the goods, loses some part of its heat. And in proportion to the quantity of water used, to the number of the extracts that have been made, and according as the mashes have more or less consistency, in the same time do they part with more or less of their heat. Observations made separately upon strong and small beer, have shewn the proportions of this loss to be as follows:
For strong beer.
Mashes2d3d4th5th
Heat lost8°12°8°8°
For small beer.
Mashes2d3d4th
Heat lost8°16°20°
A grist not perfectly malted, or one which contains many hard corns, disappoints the expectation of the computed degree, as the volume cannot be such as was estimated from an equal dryness of true germinated grain. It has been observed, that, in perfect malt, the shoot is very near pressing through the exterior skin. By so much as it is deficient in this particular, must it be accounted only as dried barley, or hard corn. I know no better way of judging what proportion of the corn is hard to what is malted, than by putting some in water, the grains not sufficiently grown will sink to the bottom. Were this to be done in a glass cylinder, the proportion between the hard and malted corn might be found with exactness.—The unmalted parts being estimated with regard to their volume, as barley, a quarter of them will be to the barrel of water as 1,56 to 131. Supposing, therefore, that, in the brown beer grist, before mentioned, the proportion of hard corns is of two quarters out of eleven, to discover the true volume of such a grist, the following rule may be used.
2 quarters of hard malt
9 quarters of true malt1,56 volume of
1,74 volume at 130° of dryness—— 1 quarter
——3,12
15,66
3,12 volume of 2 quarters of hard corn
Total——
numb. 11) 18,78 (1,70 true volume of one quarter of this malt to one barrel of water, and consequently the eleven quarters will fill a space equal to that of 6,47 barrels.
By means of this rule, we may find what increase of heat any proportion of hard corns will occasion, as will be seen in the following table.
Proportions of hard corns1/41/61/81/161/32of the grist
Greater heat of the mash4°3211/2degrees.
But the brewing of such malt ought to be avoided as much as possible, as the hard parts afford no strength to the extract.
If a grist is not well and thoroughly mashed, the heat not being uniformly distributed in the different parts of the extract, the liquor of the thermometer, when placed in the running stream of the tap, will fluctuate, and, at different times, shew different degrees of heat. In this case, the best way is to take the mean of several observations, and to estimate that to be the true heat of the mash.
If the gauges of the coppers are not exactly taken, a variation must be expected.
Though the small and hourly variations in the state of the atmosphere have but little influence upon our numbers, a difference will be observed in any considerable and sudden changes either of the heat or of the weight of the air. Our instruments, and in particular the thermometer, are supposed to be well constructed and graduated. If the water cooled in with is more or less hot than estimated, or if the time of mashing or standing is either more or less than was allowed for, the computation must be found to vary from the event.
While the malt is new, if the fire it has received from the kiln has not sufficiently spent itself, this additional heat is not easily accounted for. This is likewise the case, when malt is laid against the hot brickwork of coppers; and, on the contrary, a loss of dryness may be occasioned, if the store rooms are damp.
The artist should be attentive to all these incidents; the not pointing them out might appear neglectful; enumerating more would exceed the bounds of use.
Small grists brewed in large utensils lose their heats more readily, by laying thin, and greatly exposed to the air; and, on the contrary, a less allowance, for the loss of heat, is required in large grists, and to which the utensils are in proportion.
This really is the only difference between brewings carried on in large public brewhouses, and those made in small private places, in other respects constructed upon the same plan, and with an equal care. Prejudice has propagated an idea, that where the grists are large, and the utensils in proportion, stronger extracts could be forced from the malt, in proportion to the quantity, and that more delicate beers could be made in smaller vessels less frequently used. These assertions, from what has been said, will, I hope, need no farther enquiry: the degrees of heat for the extracts are fixed for every intent, and it cannot be advantageous, by any means, to deviate from them. Brewings will most probably succeed in all places, where the grist is not so large as to exceed the bounds of man’s labour, and not so small as to prevent the heat from being uniformly maintained. The disadvantages are great on all sides, when a due proportion is not observed between the utensils and the works carried on.
It will now be proper to continue the delineation of our two brewings, and to put all the circumstances relating to them under one point of view.
A brewing for porter or brown strong beer, computed for 40 degrees of heat in the air.
11 quarters of malt, dried to 130 degrees, 132 pounds of hops for 27 barrels 1/2, to go out at 3 worts, 31 Inches above brass.
Volume of grist6,32
Water for first mash16,00
——
22,32
6,32Volume of grist6effervescing degrees.
3 3degrees for hard corns.
—— ——
18,96 9degrees equal to 2 inches 1/4 less cooling in for the first mash, (see page 152.)
7Effervescence, per table.
——
22,32) 132,72(6 degrees of heat gained in the first mash by effervescence.
13392
Mashes 1st2d3d4th5th
Deg. of heat, 157°158°162°164°165°See p. 280.
Barrels of water used, 1681299See p. 284.
Quantity ooled in by calculation, 3/422½22See p. 284.
Boiling water by calculation; ——————————
barrels, 15¼69½77
Allowances for incidents,}32G. C.L. C.L. C.L. C.
A brewing for common small beer, computed for 60 degrees of heat in the air.
6 quarters of malt dried to 130 degrees; 36 pounds of hops;
30 barrels 3/4 to go out 56 inches above brass.
Grist3,42
Water)14,50
——
17,92
Volume of grist3,42
3
——
10,26 4° for effervescence.
7effervescing degree 1° for hard corns
for malt at 130 3° for new malt hot
——(see table page 292.) —
8° to be deduced
17,92) 71,82(4 degrees of heat from the first
7168gained in the mash cooling in.
——by effervescence.
14
Mashes1st2d3d4th
Deg. of heat.154166170174See p. 248.
Whole quantity of water used, barrels14½14½1111See p. 280.
Quantity to be cooled in, barrels3½3¼2½2¼See p. 280.
Boiling water by calculation————————
charged, barrels1111¼8½8¾See p. 280.
Allowances for incidents;
inches;less 2;more 2;more 4;more 5.
These computations, perhaps, will appear more troublesome than they really are; but, besides the facility which exercise always gives for operations of this kind, the satisfaction of proceeding upon known principles, will, I hope, encourage the practitioner to prefer certitude to doubt. One advantage must greatly recommend it, and at the same time secure the uniformity of our malt liquors; tables for each sort and season may be made beforehand, and will serve as often as the circumstances are the same. The trouble of the computations will by that means be saved, and by collecting together different brewings of the same kind, the artist will, at any time, have it in his power to see what effect the least deviation from his rules had upon his operations, and to what degree of precision he may hope to arrive.
That nothing may be wanting in this work, to facilitate the intelligence thereof, I shall insert the method of keeping the account of actual brewings, made according to the computations I have here successively traced down. The first column contains the charges of the coppers, and the numbers computed; the next, the brewings made from these numbers, with their dates, and the degrees of heat found by observation; the variations occasioned by unforeseen incidents are supposed to be allowed for, at cooling in, by the artist, upon the principle, that each inch of cooling in answers to four degrees of heat. Noting in this manner the elements of every brewing we make, when the drink comes into a fit state for use, we are enabled to compare our practice with the principles which directed it; by this means, experiments constantly before our eyes will be the most certain and best foundation for improvement.
Small Beer. Heat of air 60 Degrees. 6 quarters of Malt, 36lb. of Hops, for 30 Barrels 3/4, to go out 56 Inches above Brass.
Observations.
1760. June. 27. 1760. June. 30. 1760. Aug. 3. 1761. July. 3. 1761. July. 3.
1st Liquor. Charge great copper, 2 inches 1/2 above brass; cool in to 13 inches 1/2 above brass, rake 1/2 hour, mash 1 hour, stand 1 hour 1/2, heat of the extract intended 150 degrees. } 151149150153150
2d Liquor. Charge great copper 7 inches above brass, cool in to 13 inches 1/2 above brass, mash 3/4 hour, stand 3/4 hour, heat intended 162 degrees—1 wort came in 33 inches above brass, boiled 1 hour 1/2, went out 28 inches above brass. in to 13 inches 1/2 above brass, } 161163163148162
3rd Liquor. Charge little copper 3 inches 1/2 above brass, cool in to 13 inches above brass, mash 1/2 hour, stand 1/2 hour, heat expected 166 degrees—2 } 16616516516715
4d Liquor. Charge little copper 10 inches 1/2 above brass, cool in to 13 inches above brass, mash 1/2 hour, stand 1/2 hour, heat expected 170 degrees—2 wort came in 39 inches above brass, boiled down to 28 inches above brass. } 16616516516715
Length 31 barrels.
Porter. Heat of the Air 40 Degrees. 11 quarters of Malt, 132lb. of Hops for 27 Barrels 1/2, to go out at 3 Worts, 31 Inches above Brass.
1761. Nov. 20. 43° 1761. Nov. 3. 35° 1761. Nov. 3. 40°
1st Liquor. Charge great copper 13 inches above brass, cool in to 17 inches 1/2 above brass, rake 1/2 hour, mash 1 hour, stand 1 hour 1/2, extract expected 153 degrees. } 153151154
2d Liquor. Charge little copper 2 inches 1/2 below brass, cool in to 3 inches above brass, mash 3/4 hour, stand 3/4 hour, heat expected at the tap 154 degrees—1 wort came in great copper 16 inches above brass, boiled 1 hour, went out 13 inches above brass. } 155157153
3d Liquor. Charge little copper 10 inches above brass, cool in to 16 inches above brass, mash 1/2 hour, stand 1/2 hour, the tap to come down 158 degrees—2 wort came in great copper 11 inches above brass, boiled 2 hours, went out 5 inches above brass. } 157157158
4th Liquor. Charge little copper 1 inch 1/2 above brass, cool in to 6 inches 1/4 above brass, mash 1/2 hour, stand 1/2 hour, to come down 160 degrees. } 161160161
5th Liquor. Charge little copper 1 inch 1/2 above brass, cool in to 6 inches 1/4 above brass, mash 1/2 hour, stand 1/2 hour, tap to come down at161 degrees—3 wort came in 25inches above brass, went out 13 inches above brass. } 160161160
SECTION XIV.
Of the disposition of the Worts when turned out of the Copper, the thickness they should be laid at in the Backs to cool, and the heat they should retain for fermentation, under the several circumstances.
When a process of brewing is regularly carried on with two coppers, the worts come in course to boil, as the extracts which formed them are produced. It would be tedious and unnecessary to describe the minutest parts of the practice; which, in some small degree, varies as brewing offices are differently constructed, or the utensils are differently arranged. Without the assistance of a brewhouse, it is perhaps impossible to convey to the imagination the entire application of the rules before laid down, but with one, I hope they need little, if any, farther explanation.
The worts, when boiled, are musts possessing an intended proportion of all the fermentable principles, except air; this was expelled by fire, and until their too great heat is removed, cannot be administered to them.
In musts, which spontaneously ferment, the external air excites in their oils an agitation, which, heating and opening the pores of the liquor, expands and puts in action the internal air they possess. The case is not exactly the same with regard to those musts which require ferments. The air wanted in boiled worts must be supplied by the means of yeast. Was the heat of the wort such, as to occasion the immediate bursting of all the air bubbles contained in the yeast, an effervescence rather than a fermentation would ensue. Now a heat superior to 80 degrees has this effect, and is therefore one of the boundaries in artificial fermentation; 40 degrees of heat, for want of being sufficient to free the air inclosed in the yeast bubbles, and to excite their action, is the other. Within these limits, must the wort be cooled to; and the precise degree, which varies according to the different circumstances they are in, and to the intent they are to be applied to, is, together with the means of procuring this heat, the purport of this section.
Worts, when in the copper, boil at a heat somewhat superior to that of 212 degrees; the more this is exceeded, the stronger the liquor is. The instant the wort is suffered to go out of the copper, it loses more heat than in any other equal space of time after it has been exposed to the air. In the course of the natural day, or in 24 hours, the heat of the air varies sometimes, (especially in summer) as much as 20 degrees. If the wort, after having reached the lowest heat in this interval, was suffered to remain in the coolers, till the return of a greater in the air, it would be influenced by this increase, expand, and be put in action; and, should there be at this time any elastic air in any part of the coolers, which sometimes happens, either from the sediment of former worts, from the backs not being clean swept, or from the wood being old and spungy, the wort supposed to be left to cool, will, by receiving the additional heat from the air, and blending with the incidental elastic air adhering to the coolers, bring on, in a lower degree, the act of fermentation; an accident by the artist called the backs being set.
For this reason, a wort should never be suffered to lay so long as to be exposed to the hazard of this injury, which generally may happen in somewhat more than twelve hours. Thus are we directed to spread or lay our worts so thin in the backs, as they may come to their due temperature within this space; in summer it is sufficient if the backs be covered; in winter a depth of two inches may oftentimes be allowed with safety.
From the inclination of the coolers or backs to the place, where the worts run off, from their largeness, or from the wind and air warping them, a wort seldom, perhaps never, lays every where at an equal depth, and cannot therefore become uniformly cold in the same space of time. This renders the use of the thermometer difficult, though not impracticable. To supply the want of this instrument with some degree of certainty, the hand intended to feel the worts, is brought to the heat of the body, by placing it in the bosom, until it has fully received it. Then dipping the fingers into the liquor, we judge, by the sensation it occasions, whether it is come to a proper degree of coolness to be fermented. As the external parts of our bodies are generally of about 90 degrees of heat, some degree of cold must be felt, before the worts are ready for the purpose of fermentation. But that degree varies for different drinks, and in different seasons. I will endeavour to point out the rules to form a judgment for the heat of small beer worts. A greater precision, both for that and for other drinks, will be found in the following table.
In July and August, no other rule can be given, than that the worts be got as cold as possible. The same rule holds good in June and September, except the season is unnaturally cold. In May and October, worts should be let down nearly thirty degrees colder than the hand; in April, November, and March, the worts should be about twenty degrees colder than the hand, and only ten in January, February and December.
It may perhaps be thought that the heats here specified are great, but worts cool as they run from the backs to the working tuns, they are also affected by the coldness of the tuns themselves, and perhaps these circumstances are not so trivial, but that an allowance should be made for them. In general, the heat of no must should exceed 60 degrees, because fermentation increases this or any other degree, in proportion to that, under which this particular part of the process begins. To render the thermometer more useful, and to suit it to our conveniency, we have before supposed every first mash for common small beer to be made at four o’clock in the morning: in this case, and where the worts are not laid to cool at more than one inch in depth, the following table may be said to be a measure of time, the first and last worts for this drink should be let down at.
A TABLE, shewing nearly the times the first and last worts of common small beers should be let down in the working tuns, supposing the first mash of the brewing to be made at four o’clock in the morning, and no uncommon change happens in the heat of the air.
Air1st Wort.2nd Wort.
A ╭ │ │ │ │ │ │ │ ≺ │ │ │ │ │ │ │ ╰ 303 o’clock. ╮ │ │ │ │ │ │ │ ≻ │ │ │ │ │ │ │ ╯ B 5 o’clock. ╮ │ │ ≻ │ │ ╯ C
353½6½
404¾8
454¾9¼
505½11½
556½1½╮ │ │ │ ≻ │ │ │ ╯D
607½2½
6582½
708½3
7593
8094
A: Heat of the air at 8 o’clock in the morning. B: Hours in the afternoon, same day as brewing began. C: Hours in the afternoon. D: Hours of the next morning.
Small beer worts being nearly alike in consistency, the necessary variations from this table must be less frequent. It is true, some difference may happen from the exposition of a brewhouse, or from other circumstances, admitting more or less freely the intercourse of the air, and be such as might alter, upon the whole, the times set down in the preceding page. Brown beer worts, which are more thick and glutinous, and especially amber worts, which are stronger still, will require other and longer terms to come to their due temperature, to be fermented at; but when once observed and noted, according to various degrees of heat in the air, at 8 o’clock each morning, the conveniency of these observations must be such, in this business, which requires long watchings and attendance, that no arguments are necessary to recommend what is rather indulgence than industry.
A TABLE shewing the degrees of heat worts should be at, to be let down from the coolers into the working tuns, according to the several degrees of heat in the air.
Heat of the air. Common small.All-keeping beers.Amber or ales.
25 755955
30 705654
35 655353
40 605052
45 555051
50 505050
55}In these cases, when the medium heat of the air is greater than that which the worts should ferment bring them as near as possible to their temperature. It has been observed, that the coldest part of the natural day is about one hour before sun rising.
60
The consequences of worts being set to ferment at, in an undue heat, are the following. In strong beers, or such as are intended for long keeping, if the worts be too cold, a longer time is required for their fermentation, and the drinks grow fine with more difficulty; if, on the contrary, they are too hot, acidity, and a waste of some of the spiritous parts must ensue. Either of these disadvantages appears more conspicuous in common small beer, as, in winter, this drink is seldom kept a sufficient time to correct the defect, and in summer, from being too hot, it becomes putrid, or, in the terms of the brewery, is hereby foxed.
SECTION XV.
Of Yeast, its nature, and contents, and of the manner and quantities in which it is to be added to the worts.
Musts, or worts, though ever so rich, when unfermented, yield no spirit by distillation, nor inebriate, if drank in any quantity. The oils, as yet not sufficiently attenuated for this purpose, become so only by fermentation. Air is absolutely necessary for this process, in the course of which, some of the aerial parts mixing with, and being enveloped by, oils greatly thinned, are enclosed in vesicles not sufficiently strong to resist the force of elasticity, or prevent a bursting and explosion. In the progress of the act, the air joins with oils both coarser, and charged with earthy particles, a coat is formed capable of resisting its expansion, and if the bubbles cannot come to a volume sufficient to be floated in and upon the liquor, they sink to the bottom, and take the appellation of lees of wine. Between these two extremes, there is another case, when the bubbles are sufficiently strong to hold the air, but not weighty enough to sink. After floating in, they emerge, and are buoyed upon the surface of the liquor, and there remaining entire, are termed the flowers of wine. Both lees and flowers are, therefore, vesicles formed out of the must, filled with elastic air, and, either separately, or when mixed together, they obtain the general denomination of yeast. We have often mentioned the power of fire, in driving the air out of worts. Yeast, fraught with the principle now wanted for fermentation, is, therefore, the properest subject to be added to the must; but its texture is various, in proportion to the different heats of the extracts it was formed from. Keeping drinks, extracted with hotter waters, yield yeast, the oils of which have a greater spissitude. It is consequently slower, more certain, and most fit to promote a cool and gentle fermentation. That, on the contrary, which is produced from small beer, being weak, and acting at once, is apt to excite a motion like that of effervescence; such yeast ought, therefore, not to be used, but when there is no possibility to obtain the other. The longer wines or beers are under the first act of fermentation, the greater variety will be found in the texture of the bubbles, which compose their flower and lees. Wines made out of grapes, in general, require a time somewhat longer than the worts of malt, before this first period is at an end; and we have seen, that in them fermentation first brings forth air bubbles, whose constituent parts are most tender, and afterwards some that are of a stronger texture. As malt liquors require a less time to ferment, their bubbles are more similar: on this account, the whole quantity of yeast necessary to a wort should not be applied at once, lest the air bladders, bursting nearly in the same time, should prevent that gradual action, which seems to be the aim of nature in all her operations. Keeping beers, formed from low dried malts, occasion the greatest variety of heat in the extracts, and from hence these musts form yeast, whose bubbles differ most in magnitude and strength. A drink, then, properly made from pale malt, nearly resembles natural wines, especially when they are so brewed as to require precipitation to become transparent. Cleansing is dividing the drink into several casks; this checks the motion occasioned by fermentation, and consequently retards it. To prevent this from being too sensibly felt, some yeast should be put to the drink, before it is removed into the casks. As the constituent parts, in strong beers, are more tenacious than in small, and require a greater motion to entertain the fermentation, the drinks, before they be thus divided, should, besides the addition of the yeast, be well roused with a scoop, or by some other means, for one hour. This not only blends all the parts together, but attenuates and heats the liquor, and makes it more ready to begin to ferment again, when in the casks. One sixth part of the whole of the yeast used is generally reserved for this purpose; and the remainder is equally divided as the worts are let down. It must be observed, that this stirring, though as necessary to small, as to strong drinks, is only to be continued for a space of time proportioned to their strength. We have before seen, when a grist of malt is entirely extracted to form common small beer, soon to be expended, one gallon of yeast to eight bushels of grain affords a sufficient supply of air to perfect the fermentation. This takes place when the heat of the air is at 40 degrees, but, at the highest fermentable degree, experience shews, that half that quantity is as much as is necessary. For some ales, the whole virtue of the malt is not extracted, and what remains is appropriated to the making of small beer: the quantity of yeast used for these drinks must be only in proportion to the strength extracted. From these premises, the following tables have been formed, exhibiting the quantity of yeast proper for the several sorts of drinks, at the different heats of the air.