Distillable

That may be distilled. Distillation, n. [Fr., from Lat. distillatio.] ( Chem.) The proce of evaporating a fluid by means of heat, and afterwards condensing it into a liquid. Its object is to separate one substance from others with which it may be mixed; and the po ibility as to whether a substance can be distilled depends upon the temperature at which it evaporates. It is not known when distilled spirits were first made; but the discovery is usually attributed to the alchemists, who called it aqua vitæ. In the laboratories, D. is commonly performed by means of a still like that represented in Fig. 837, in which A is a copper IMG:content-0643.png:[blocks in formation] boiler containing the water to be distilled; Bis the head of the still, which lifts out at b, and is connected by the neck C with the worm D, a pewter pipe coiled round in the tub E, and i uing at F. The steam from the boiler, pa ing into the worm, is condensed to the liquid state, being cooled by the water in contact with the worm; this water becoming heated, pa es off through the pipe G, being replaced by cold water, which is allowed to enter through H. A rosette gas burner, K, on Bunsen's principle, is very convenient for a small still of that description. (Applied Chem.) The proce of D. is carried on upon the most extensive scale for the production of ardent spirits in the distilleries . Under the words Alcohol, Fermentations, Wine, ., will be found some details bearing upon the nature, sources, and production of spirituous liquors; in the present article, therefore, we shall limit ourselves to an outline of the different proce es of D. - There are two distinct operations in the production of ardent spirits: the one is the conversion of certain vegetable principles into alcohol; and the other, the separation of the alcohol from the other substances with which it is nece arily blended during its production. The vegetable principle which is e ential to the formation of alcohol is sugar ; and this is sometimes used directly , as where mola es and analogous saccharine products are subjected to immediate fermentation; or it is indirectly obtained by subjecting amylaceous grains to certain proce es, by which the starch they contain is first converted into sugar, and then that sugar afterwards alcoholized. In our distilleries the latter alternative is adopted; and various kinds of grain, but chiefly corn, barley, wheat, and rye, with more or le malt, are subjected to the operation of mashing . For this purpose the ground grain and the bruised malt are duly mixed, and infused under constant agitation in a proper quantity of hot water in the mash - tun ; the wort is then run off, and fresh water added, till the soluble materials of the grain are extracted. The mixed worts, or wash , thus obtained, is run into the fermenting vats, where, mixed with a small quantity of yeast, it is subjected to the proce of fermentation, which continues from six to ten or twelve days, the time required for its completion varying with the ma of liquid, and with the temperature of the atmosphere. During mashing, the starch pa es into sugar, and during fermentation the sugar changes into alcohol; the consequence of which is, that the wash gradually decreases in density, or attenuates ; and as soon as this attenuation has reached its maximum, which may be determined by the hydrometer, it should be distilled in order to prevent the commencement of acetic fermentation. In all large distilleries there are two sets of stills: one for the purpose of distilling from the wash a weak spirit, technically called low wines ; and the other for re-distilling (or rectifying ) the low wines. In these D. there pa es over, along with the first and last portions of the spirits, a peculiar volatile oil of a disagreeable flavor and odor, and rendering the weaker spirit milky. These portions are called faints , and are carefully mashing, fermentation, and distillation have been respectively conducted; theoretically, 100 pounds of sugar are convertible into about 51 of alcohol and 49 of carbonic acid. The quantity of alcohol to be procured from different kinds of grain will also depend upon the same causes, and upon the quantity of sugar, and of starch and gum convertible into sugar, which each may contain. According to Hermstædt, 100 pounds of starch should yield 35 pounds of real alcohol; and 100 pounds of the following grains should yield the following quantities of spirit of the specific gravity of 0-9427; that is, of spirit containing 45 per cent. of real alcohol; namely, wheat 40 to 45 pounds, rye 36 to 42, barley 40, oats 36, buckwheat 40, maize 40. Sometimes, though rarely, malt only is used in the distillery, in which case the distiller calculates on obtaining two gallons of whisky of proof-strength from each bushel of malt. D. , destructive. See DESTRUCTIVE DISTILLATION. Distillatory, a . [Fr. distill a to ire .] Pertaining to distillation; used in the proce of distilling; as, " distil latory ve els."