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- DISTILLATION. · short time, and when it has sprung ART. II.
i up, it is removed and washed, or MALTING,
otherwise oleaned, and then dried MALTING consists in making in the kiln like other malt. In this grain germinate artificially to a country the process, as described certain extent, and then stopping by an accurate chemist, is as folthe process. Every species of grain lows:may be subjected to it, but some The barley is steeped in cold species answer the purposes of the water for a period which (as regu-, distiller and brewer much better Jated by law) must not be less than than others, and in this country in forty hours; but beyond that pegeneral only barley is malted. riod the steeping may be continued With some species of grain, such as long as is thought proper. Here as Indian corn, the germination it imbibes moisture, and increases must be carried to a considerable in bulk; while at the same time • extent, and it is actually buried a quantity of carbonic acid is emit
under the earth, or sown for a ted, and a part of the substance of
the husk is dissolved by the steep- begins gradually to absorb oxwater. The proportion of water ygen from the atmosphere, and imbibed depends partly on the to convert it into carbonic acid ; barley, and partly on the length at first very, slowly, but afterof time that it is steeped. From wards more rapidly. The temthe average of a good many perature, at first the same with trials, it appears that the medium that of the external air, begins increase of weight from steeping slowly to increase; and in about may be reckoned 0.47; that is to ninety-six hours the grain is, at an say, every 100 pounds of barley average, about 10° hotter than the when taken out of the steep weighs surrounding atmosphere. At this 147 pounds. The average increase time the grain, which had become of bulk is about a fifth; that is to dry on the surface, becomes again say, that 100 bushels of grain, after so moist that it will wet the hand, being steeped, swell to the bulk of and exhales at the same time an 120 bushels. The carbonic acid agreeable odour, not unlike that emitted while the barley is in the of apples. The appearance of this steep is inconsiderable; and it is moisture is called sweating. Asmall probable, from the experiments of portion of alcohol appears to be Saussure, that it owes its forma- volatilized at this period. The tion, at least in part, to the oxygen great object of the maltmen is to held in solution by the steep-water. keep the temperature from be
The steep-water gradually ac- coming excessive. This they do quires a yellow colour, and the by frequent turning, The tempepeculiar smell and taste of water rature which they wish to preserve in which straw has been steeped. varies from 550 to 620, according The quantity of matter which it to the different modes of malting holds in solution yaries from 1-50th pursued.. to 1-100th of the weight of barley. At the period of the sweating the It consists chiefly of an extractive roots of the grains begin to appear, matter, of a yellow colour and at first like a small white promidisagreeable bitter taste, which nence, at the bottom of each seod, deliquesces in a moist atmosphere, which soon divides itself into three and contains always a portion of rootlets, and increases in length nitrate of soda. It holds in solu- with very great rapidity, unless tion most of the carbonic acid dis- checked by turning the malt. engaged. This extractive matter About a day after the sprouting is obviously derived from the husk of the roots, the radiments of the of the barley, and is that substance future stem, called acrospire by the to which the husk owes its colour.' maltsters, may be seen to lengthen. Accordingly, grain becomes much It rises from the same extremity paler by steeping.
of the seed with the root, and adAfter the grain has remained a vancing within the busk, at last sufficient time in the steep, the issues from the opposite end: but water is drained off, and the barley the process of malting is stopped thrown out of the cistern upon the before it has made such progress. malt-floor, where it is formed into As the acrospire shoots along a rectangular heap, called the the grain, the appearance of the couch, about 16 inches deep. In kernel, or mealy part of the corn, this situation it is allowed to re- undergoes a considerable change. main about 26 hours. It is then the glutinous and mucilaginous turned, by means of wooden sho- matter is taken up and removed; vels, and diminished a little in the colour becomes white, and the depth. This turning is repeated texture so loose that it crumbles twice a day or oftener, and the to powder between the fingers. grain is spread thinner and thin. The object of malting is to proner, till at last its depth does not duce this change: when it is acexceed a few inches.
i complished, which takes place When placed on the couch, it when the acrospire has come nearly
to the end of the seed, the process These two, in reality, include the is stopped by drying the malt whole real loss of weight which upon the kiln. The temperature barley sustains when malted. at first does not exoeed 90°; but What is lost in the steep, being it is raised very slowly up to 1400, husk, need scarcely bo reckoned. or higher, according to circum- · The roots appear, from the prostances. The maltis then cleaned, cess, to be formed chietly from the to separate the rootlets, which are mucilaginous and glutinous parts considered as injurious.
of the kernel. The starch is not Such is a short sketch of the employed in their formation ; but process of maltiny. Barley, by undergoes a change, intended no being converted into malt, gene- doubt to fit it for the future nourally increases two or three per rishment of the plunula. It accent, in bulk; and loses at an quires a sweetish taste, and the average about a fifth of its weight, property of forming a transparent or 20 per cent. But of these 20 solution with hot water. In short, parts 12 are to be ascribed to kilo, it approaches somewhat to the nadrying, and consist of water, which ture of sugar; but is much more sothe barley would have lost had it luble, and much more easily decombeen exposed to the same tempe- posed, than that principle. From rature : so that the real loss does the experiments of Saússure on not exceed eight per cent. From the conversion of starch into sugar, a good many trials, made with as there is reason to conclude that much attention to all the circum- this change is brought about by stances as possible, the following the combination of the starch with seems to be the way of accounting water. The action of hot water on for this loss :
barley-meal seems gradually to Carried off by the steep-water .. 1.5
induce a similar önc.'. Dissipated in the floor. .........3.0
Our plate represents a side Roots, separated by cleaning....3.0 view of a malt-kiln, in which the ..........0.5 malt is dried by heated air, but
in which the air necessary for the .8.0
combustion of the fuel descends The loss on the floor ought to be through the grate. a, the fire. b, entirely owing to the separation the gráte. c, the door of the furof carbon by the oxygen of the pace. d, the door of the ash-pit. atmosphere ; but were this the e, the air cylinder. f, the ash-pit. only cause, it would be much g, the end of the air cylinder entersmaller than three per cent. Two ing the space below. h, the kila other causes concur to produce head, which is composed of tiles this loss;-1. Many of the roots perforated with small holes lying are broken off during the turning on the joists i, and supporting the of the malt; these wither and are malt k. 1, l, the windows, through lost, while others grow in their which a current of air may freely place. 2. A certain portion of the enter or escape. m, the air outlets seeds lose the power of germi- above. If a distiller finds his nating, by bruises or other acci- works so relatively situated that dents, and these lose a much be can lead the air cylinder of his greater portion than three per malt-kiln through the flue of his cent. of their real weight, From still or inash boiler furnace, the a good many trials, made with as expense of fuel for drying malt much care as possible, I am dis will be saved... posed to conclude that tho quantity of carbon separated during the whole process of malting, by the
ON THE CUTTING OF STEEL formation of carbonic acid gas,
BY SOFT IRON. does not exceed two per cent., and The fact that soft iron made to that the weight of the roots formed revolve very rapidly will cut steel, amounts often to four per cent. has long been known. The follow
ing is an interesting account of the the operation. The impulse against mode by which it is effected, as the steel is so strong, that in sevewell as a good explanation of the ral instances it was thrown against principles of the operation :
the opposite side of the room with It seems to have been discovered a velocity that might not have been by the Shakers, who are remark- without danger to a person standable for the neatness and expert- ing in the way. It may be said, ness of their mechanical opera. I believe, with safety, that none of tions. As it is desirable that the the ordinary mechanical operations experience of others on this sub-' commenced upon cold and hard ject should be made known, I will steel, will divide it with so much How add, that in Jupe last I saw rapidity as this mode of applying Professor Robert Hare, at Phila- soft iron. After all, it is evident delphia, execute, with a common that it is only a peculiar method of foot-lathe, operations similar to cutting red hot, or possibly white those described by Mr. Daggett: hot steel; for the mechanical force they were, however, less energetic produces these degrees of heat, and decisive, as the machine did and it is one of the best methods not produce so rapid a motion as of evolving heat by mechanical that of Mr. Barnes.
impulse. - The steel of course loses I have, however, since repeated- its temper at the place of section, ly seen the experiment succeed, in and there only; for the softening the most perfect manner, at the extends but a little way, and is manufactory of arms belonging to limited to a parrow portion, markEli Whitney, Esq., near this town by the iris colours known to be (New Haven, Connecticut). As produced by heat upon steel. water power is here applied with The iron plate, as Mr. Daggett grcat facility and energy, a wheel states, becomes only warm, and of soft and very thin plate iron, six wears away, only very slowly; yet inches in diameter, and furnished it does, wear, for the edges are left with an axis, was made to revolve rough, and the channel of section · with such rapidity that the motion in the steel cxbibits, with a mag
became entirely imperceptible, and nifer, minute striæ or grooves, · the wheel appeared as if at rest. running in the direction of the When pieces of the best and hard wheel's revolution.". I know not est steel, such as files, and the that there is any reason to suppose steel of which the parts of gun- any peculiar electrical phenomelocks are made, were held against non, except that electricity always the edge of the revolving soft iron accompanies - heat. It is plain plate, they were immediately cut from the important use made of by it, with a degree of rapidity this mode of cutting steel by the which was always considerable, Shakers and by Mr. Barnes, that but which was greater as the pieces it may be of considerable practical of steel were thinner; pieces as importance. : thick as the plate of a common : As a philosophical experiment joiner's saw, were cut almost as it is highly interesting: and it rerapidly as wood is cut by the saw mains yet to be shown, why, the itself. Considered as an experiheat evolved by the impulse should ment merely, it is a very beautiful nearly all be concentrated in the one, and in no degree exaggerated steel, and be scarcely perceptible in Mr. Daggett's account: there is in the iron: neither is it perfectly a very vivid coruscation of sparks, clear that even ignited steel should flying off in the direction of tan-. be so casily cut by the impinging gents to the periphery of the, cut- of soft iron. No smith probably tiny-wheel; and an intense igni. ever thought of attempting to die tion of the steel; extending for a vide steel by applying an iron. considerable distance ahead of the tool. --- Silliman's Journal, vol. yii. section, and on its sides, attends p. 342.