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boiler before it passes off, by which the whole mass of fluid in the boiler is heated at once, and the heat may be maintained with great regularity, while a much less quantity of fuel will suffice. The brick-work surrounding the boiler reaches as high as the circle k k.

The worm is generally made of tin or pewter, and is the same as that in common use, except that at the commencement 1, where it is connected with the beak of the head of the boiler, it is wider than they were formerly made, and tapers gradually towards the discharging extremity m. The reason of this is evident, because vapor, only partly condensed, requires more room than where the whole is fluid. The refrigeratory, or vessel A B, is kept constantly filled with cold water; this is effected by a tube n, which descends and opens nearly at the bottom of it, and brings a supply of cold water from a greater elevation; while another tube, r, conveys the hot water with equal rapidity from the top. By this means the condensation is so complete, that the spirit discharged at m exhales little or no odor. As it is often not possible to have the water from a greater elevation than the refrigerator, without raising it by mechanical means, the following plan, by Alexander Johnston, is highly entitled to attention, as in it the syphon is applied to the worm-tube as a refrigerator; and water is conveyed in any quantity to a worm-tub of the largest dimensions, if perfectly air-tight; it is represented at in the same plate A, is the feed pipe of cold water. B, the hot water, or waste pipe, the end of which must be abouttwo feet below the feed pipe, to make it act with full effect. When the work is commenced, the cocks must be shut, and the tub filled through a hole at the top, and of course, both pipes: and when full, the hole at the top is to be stopped, and the cocks opened together; the water will then commence running, and continue as long as the supply holds good, as it acts in every respect on the principle of a syphon. By this means pumps, horse-mills, and other machinery, are rendered unnecessary for that purpose. The application of this improvement is simple, and executed at a very little expense. The saving for the city of Dublin alone, is calculated at upwards of 100 horses per annum.

With respect to the usual mode in which distillation is conducted in the great public distilleries, the most interesting account that has been communicated to the public, is that contained in the deposition of James Forbes, of Dublin, who was for many years concerned in a large distillery. It is from the Appendix to the Fifth Report of the Commissioners of Enquiry into the Fees, &c., received in the public offices of Ireland; which report was printed by order of the house of commons.

'The corn is first ground, then mashed with water, and the worts, after being cooled, are set for fermentation, to promote which, a quantity of barm is added to them, and they become wash; the wash is then passed through the still, and makes singlings, and these, being again passed through the still, produce spirits; the latter part of this running, being weak, is called feints. When singlings are put into the still, a small

quantity of soap is added, to prevent the' stil! from running foul; a desert spoonful of vitriol well mixed with oil is put into a puncheon of spirits, to make them show a bead when reduced with water: this is only done with spirits intended for home consumption, and no vitriol is used in any other part of the process. In this distillery, the former practice was to use about one-fourth part of malt, and the remainder a mixture of ground oats and barley, and oatmeal; latterly the custom has been to use only as much as would prevent the kieve (mash-vat) from setting. He had found that malt alone produced a greater quantity of spirits, than the mixture of malt and raw corn of the same quality with that of which the malt had been made. He generally put from fifty to fifty-four gallons of water to every barrel of corn of twelve stone (14 lb. to the stone). Each brewing was divided into three mashings, nearly equal: the produce of the two first was put into the fermenting backs; and the produce of the last, which was small worts, was put into the copper for the purpose of being heated, and used as water to the next day's brewing, when as much water was added as would make, with the small worts of the brewing, fifty-four gallons to each barrel of the corn. The kieves were so tabulated, that he always knew the quantity of worts which would come off at each mashing. Their strength he ascertained by Saunders's saccharometer, and at the above proportions he obtained, from a mixture of the two first worts, an increase of gravity from twenty pounds to twenty-two pounds per barrel, of thirty-six gallons, above water-proof, at a temperature of about 88°. The small worts gained at the same temperature about six pounds. The grain, after the last worts were off, retained nearly the same bulk as when put into the kieve; the whole of the grain was put in at the first mashing; he never knew any grain to be added to the second mashing. The worts of the first and second mashing were run through the mashkieve into the under-back, in which state they were usually found to correspond with the computation made in the mash-kieve and underback, in the latter of which a correct gauge might be taken of them. He usually commenced brewing at six o'clock in the morning: the first worts were run off into the under-backs, and required from an hour to an hour and a half to be forced up into the cooler; the second worts came off at the end of two hours from the discharge of the first, and required about the same time to pass into the coolers. The small worts were generally let off late at night; and being then, or early on the following morning, put into the copper to be used for the next brewing, were seldom shown on the coolers. He thinks that any decrease of the worts by evaporation whilst on the coolers, must have been very inconsiderable; and that a correct gauge of the worts may be taken in the coolers as well as in the underbacks. The quantity of wash in the backs was found to be nearly correspondent with that of the strong waters which had been on the kieve and in the cooler. The fermentation of the worts was produced by means of yeast, and was in general so contrived as to be apparently kept

up for the full time allowed by law (six days): he has, however, usually had his wash ready for the still in twenty-four hours from the time in which it was set. Backs are renewed in two ways; either by additions made to them from other backs in the distillery, each supplying a certain portion of wash to the back which is next before it in the order of fermentation, while the newest and least fermented wash is replenished by worts, or, when the fermentation is down, by an entire substitution of worts. He has ordinarily, in the course of work, charged a 500 gallon still with wash, and run it off in twenty to twenty-three minutes: he has seen a 1000 gallon still charged and worked off in twenty-eight or thirty minutes. He understands that it is now the practice of some distillers, to heat the wash nearly to the state of boiling before the still is charged with it; by which means he believes the process to be accelerated by three or four minutes. He has seen a 1000 gallon still charged with singlings, and worked off in from forty to fifty minutes, and thinks a 500 gallon still requires nearly an equal time. Feints from potale (the name given to completely fermented wash) usually are run off in from six to seven minutes; making allowance for every delay, about six charges of spirits may be run off from a still of 500 gallons' contents, each charge estimated at 150 gallons. The feints were always put back into the pot-ale receiver; twenty gallons of feints is the usual quantity run from a 500 gallon still charged with singlings; he thinks there is more spirit extracted from feints than from pot-ale; there was no delay between one charge of pot-ale and another, or between one of singlings and another; the still could be cleansed in less than a minute; it very rarely occurred that the ordinary accidents which happened to the still delayed the work to any considerable degree. The still is never charged with wash beyond about seven-eighths of the still, nor with singlings beyond about four-fifths, exclusive of the head. The estimated produce (according to which the duty may be charged) is one gallon of singlings from three gallons of wash, and one gallon of spirits from three gallons of singlings, but it is very frequently some what more. Previous to the regulation (of Excise) which took place in June, 1806, from a still of 540 gallons, which is charged with 2075 gallons of spirits weekly, he has frequently drawn 530 gallons in one week, and thinks 500 gallons to be a fair average. He usually made spirits about fourteen per cent. above proof, by Saunders's hydrometer. Spirits exported by him from twelve to fourteen per cent. above proof by Saunders' and Hyatt's hydrometer, were charged in London at from twenty-four to twenty-six gallons per cent. Before he sent them to the custom-house, he either reduced them with water, or drew them at that strength from the still. To every six gallons of strong spirits, one gallon of water was added in the distillery, which reduced them to the strength usual for exportation. The reduced spirits are permitted to the king's warehouses, and the distiller given a credit for a decrease of stock equal to the quantity so permitted; by these means he has one gallon of private

spirits to dispose of for every gallon of water mixed with the spirits exported; besides this, the distiller draws back the allowance given in lieu of the malt-duty on every gallon of water added: when he warehoused spirits with the intention of afterwards using them for home consumption, he left them at their full strength.'

The absence of improvement in the process of distillation, as well as in the apparatus for effecting it, in this country, may be chiefly traced to the shackles which have proceeded from the regulations of excise, adopted and enforced for the protection of the revenue. Whether those regulations may have been indispensably requisite to that end, is, perhaps, very questionable; but it is quite certain that they have had the effect of restraining those extensive improvements in this branch of science and business, which have been almost universally accomplished, where the inventive genius of our countrymen has had free scope in the application of its powers to practical results. This is especially visible on a comparison of the means employed in France for the improvement of this branch. With an unlimited supply of the grape, a material certainly calculated to afford one of the finest spirits, they are enabled, almost at will, to effect such improvements in its quality as result from changes of process, and the adoption of superior apparatus; since, although in some respects under certain revenue regulations, they are not enforced in a manner calculated to prejudice the exercise of talent, whether mechanically or chemically applied to the art.

In the English language, too, there scarcely exists a treatise of any value on this subject; and that which has been published is little more than translations from works in the French language. There the scientific investigations of such men as Lavoisier, Chaptal, Gay Lussac, and Thenard, have laid a sure foundation for the more practical illustrations of Macquer, Dubrunfaut, Dubuisson, and others of less note, who have sent forth to the world the result of their labors.

With names as high on the list of science as our countrymen Davy, Woollaston, Dalton, Heury, Thomson, Ure, and Black, and with some of the most important departments of the art of distillation, up to the point of fermentation, as well understood, and as extensively practised as in France, the paucity of information on the subject generally, in this country, is not a little sur prising. The French distillers have brought to notice several stills of curious construction, which have had for their object the saving of time and fuel, and the production of a spirit of superio. strength and good quality. In some of these perpetual distillation has been aimed at, but it cannot be said with success. Indeed, it is difficult to conceive that the elements to be converted, and the practice necessary for their conversion, can be so nicely combined and adjusted as to bring about such a result, without a most elaborate and expensive series of machinery and vessels; costly in themselves, not easy of management, and leading to the risk of considerable loss, from some of those inconveniences and irregularities to which all complicated apparatus are subject.

A still has lately been brought forward, which

is stated to be coming into extensive use, and to comprise all the advantages of perpetual distillation without its disadvantages; uniting moderate cost, the employment alike of a single vessel and a single operation, and the most perfect facility of management, with great economy of time, fuel, and other items of expense; and, which must be a primary object with all distillers, with the production of a fine and potent spirit. It has been introduced by two French gentlemen, M. Alégre, and M. Saintmarc; and is patented in this country in the name of the latter.

On a view of the plans and descriptions of this apparatus, there seems little reason to doubt its powers and advantages, as described; and, assuming the truth of the facts stated with regard to those powers as proved in practice, the invention is entitled to great praise; and must effect an extensive revolution in distillation, both in this country and in its colonies.

The plate of DISTILLATION presents a series of figures, exhibiting the construction and practical operation of this interesting combination of chemical and mechanical power.

Fig. 1 represents a sectional view of the still, with its furnace, and an elevation or outside view of the refrigerator, or worm tub. Figs. 2, 3, and 4, are plans of three portions of the still. Fig. 5 is a perspective view of one of the double tubes or pipes. Fig. 6 is an elevation of its front exterior, and fig. 7 is an elevation of its back exterior.

FIGURE I.

A. THE FIRE-PLACE or FURNACE, above which the still is placed.

B. EIGHT COPPERS or BOILERS, surmounting each other, constituting the apparatus or still, in the form of a column or cylinder, and numbered 1 to 8; the different coppers or compartments being put together by flanches and bolts.

C. (vide fig. 6 and 7), OPENINGS or MANHOLES. tightly closed by screw boxes, or otherwise, calculated, when the still is of large diameter, to admit a person into the several coppers, No. 1 to 7, for the purpose of cleaning or repairing them; or, when on a smaller scale, intended to admit a person's arm for the same object.

D. AN EXTERIOR VESSEL, Or INTERMEDIATE WASH CHARGER, Surrounding the upper compartment of the still; and calculated to contain a quantity of wash equal to the proper charge of one copper.

E. SUPPLY PIPE communicating from the general wash charger, or vessel containing the liquid to be distilled, to the exterior vessel D; and furnished with a cock for the purpose of turning the wash into that vessel.

F. A PLUG OF VALVE fixed in the head of a pipe extending from the bottom of the vessel D into the lower part of the copper, 7; which plug or valve is raised by the aid of

G. A LEVER AND FULCRUM for the purpose of discharging the wash contained in the vessel D into the copper 7; from whence, as it reaches the upper end of the pipes H, it flows down from copper to copper, until it reaches No. 2; a quantity being displaced from the surface of the liquor in each copper equal to that which is thrown in from the copper next above.

H. FIVE PIPES, communicating from the copper, fig. 7 to fig. 6, and so on in succession, from vessel to vessel, down to fig. 2, extending from the level of the wash in one copper, marked by dotted lines to nearly the bottom of the copper below, in order to displace the warmest liquor, as shown in the description of G.

I. (Vide figs. 6 and 7), SIX PIPES FURNISHED WITH COCKS, Communicating respectively from one copper to that next be'ow, by which all the wash in the several coppers, from fig. 7 downwards, may be conveyed into the lower coppers, and finally drawn off from the lowest vessel.

K. (Vide figs. 6 and 7), SMALL TRIAL COCKS IN COPPERS 1 and 2, which, on being turned, indicate when those coppers are charged to the proper height, as denoted by the dotted lines on the same level as these cocks. They serve also as valves to admit air when the liquor is drawn off. A similar cock is likewise placed in copper, fig. 3, for the purpose last mentioned.

L. (Vide fig. 6), A SMALL PROOF COCK, placed vertically near the roof of the copper, No. 1, which, on being turned, determines by the application of a lighted taper or candle, whether or not there remains any portion of alcohol in this copper or boiler.

M. A DISCHARGE PIPE AND Cock to carry off the spent wash from the copper, fig. 1, when the spirit has distilled from it. This cock discharges down to about one inch above the crown, or highest part of the copper; and, in consequence, it is not necessary to damp the fire when it is opened.

N. A SECOND DISCHARGE PIPE AND COCK in the lowest part of the bottom, which carries off the whole contents of the copper; and, when opened, will generally require the fire to be damped, to prevent burning the bottom.

The

O. TEN DOUBLE TUBES or PIPES, of which five are fixed on the roof of copper 1, and five on that of 2. These pipes are closed at the top, and have openings in the upper part of the inner, communicating with the outer one. vapor produced from the wash in copper 1, passes through the five double tubes on the roof of that copper into the copper 2, by rising up the inner tubes, passing therefrom through the openings at the upper part thereof, and descending down the outer tubes, discharging itself into the liquid in copper No. 2, where it becomes condensed. In like manner the vapor produced in the last mentioned copper passes up the double tubes on the roof thereof, into the copper fig. 3. (For a better description of these double tubes, vide the perspective view of one of them in fig. 5; and for the plan of the coppers containing them, vide fig. 4, and their respective explanations given below).

P. FIVE SEMISPHERICAL VESSELS or DOMES (in French, CALOTTES), constructed upon, and tightly jointed to, the centres of the roofs of the several coppers, No. 3 to 7, both inclusive. These domes, except the highest, are surrounded with wash; but have internal communication only with each other, by means of pipes fixed on their centres, which pass into the pipes Q, next described.

Q. FIVE DOUBLE TUBES or PIPES (of the same

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