DIASTASE.

399

%ui'es of any kind of tweeled cloth, excepting damask. The mounting of a loom forworking diaper is, in principle, much the same as a draw-loom, but the figures being

less

extensive, the mounting is more simple, and is wrought entirely by the weaver,

unout the aid of any other person. As tweeled cloths, of any number of leaves, arefuy interwoven at those intervals when one of the leaves is raised, the woof above, andhe warp below, is kept floating or flushed, until the intersection takes place. Of con-sequence, the floating yarn above appears across the fabric, and that below longitudi-nally. Thi s property of tweeled cloths is applied to form the ornamental figures of all.'ods of tweeled goods, merely by reversing the floating yarn when necessary. In thesimpler patterns, this is effected by a few additional leaves of treddles; but when thea nge of pattern becomes too great to render this convenient, an apparatus called a backartless is employed, and the cloth woven with this mounting is called diaper. Diapersgenerally five-leaf tweels; that is to say, every warp floats under four threads of°°f, and is raised, and of course interwoven with the fifth. Thisis done either suc-j ss >vely, forming diagonals at 45° upon the cloth, or by intervals of" two threads, whichealled the broken tweel. The latter is generally, if not universally, adopted in theanufacture of diaper. The reason of preferring the broken to the regular tweel,o ar . e ornaments are to be formed, is very obvious. .The whole depending upon reversedde . st »"g to give the appearance of oblique or diagonal lines, through either, wouldt s r ) °y much of the effect, and materially injure the beauty of the fabric. The brokenDla’ ’ 0n ^ le contrary, restores to the tweeled cloth a great similarity of appearance toProd*’ ° r alternately interwoven fabrics, and at the same time preserves the facility of^ill k C * n ” ornaments by reversing the flushing. The simplest kinds of reversed tweelsDra ^ oul, d described under Textile Fabrics.c ; d -j ASTASE. This curious substance, extracted by water from crushed malt, and pre-Siad*^ from that infusion by alcohol, as is described under Fermentation, has beenfro mY' he - su ^j ect new researches by M. Guerin Varry. The conclusions deduciblej “is interesting experiments are the following:—t ato " Une part of diastase, dissolved in 30 parts of cold water, put with 408 parts of po-i„ (, starc h out of contact of air, did not exercise the slightest action upon this substance2 f '!p' 0Ursl ‘ of 63 days, under a temperature varying from 68° to 79° Fahr.hPrts r 0 l Klr ^ °f diastase do not in the course of an hour cause the globules of three' T,1 >ch h arch t0 * )Urst ’ at a temperature approaching very nearly to that of the hot watergertni . st s them into a paste. It follows that diastase acts no part in the process ofrio r n at . 10n > towards eliminating the teguments of the starch, or transforming its inte-

3. * nt ° su ° ar > anc * a g“ mm y matter assimilated by plants.

gag em laStase liquefies and saccharifies the paste of starch without absorption or disen-

4. , aat °f gas j a reaction which takes place equally in vacuo as in the open air.

'with 6.,,, i’ arts °f starch made into a paste with 39 times their weight of water, mixed14CP . , Parts of diastase dissolved in 40 parts of water, and kept for an hour between

5. * a 149° Fahr., afforded 86-91 parts of sugar.

12-25 2 aste containing 100 parts of starch, and 1393 parts of water, put in contact with68° F a r art ® diastase dissolved in 367 parts of cold water, having been maintained at

6. ““ring 24 hours, produced 77-64 parts of sugar.

the end e „P^ ece ding experiment, repeated at the temperature of melting ice, afforded at

7. ^ hours, 11-82 parts of sugar.

^“Uhtity 6 '? ost f av °rable proportions and circumstances for the production of a greatcent, 0 p su gar, are a slight excess of diastase or barley -malt (at least 25 perture b 'utter), about 50 parts of water to one of starch, arid a tempera-

c uti°n to t e n. n ani * '49“ Fahr. It is of the greatest consequence for the saccharifi-J? nt uct wfih 6 P^ ace as speedily as possible, so that the sugar produced may not be left inT® latter ; J 0110 ! 1 gummy matter (dextrine), in which case the diastase will not convert'^Itcueously EU " ar ' -lu fact, the liquefaction and saccharification should proceed

^ u liflow e f^" ar .°^ starch, prepared either with diastase or sulphuric acid, crystallizes in* jlcupes. ° r ln P r ' s ms with rhomboidal facets. It has the same composition as sugar

em* 6r a ^°u* S wio7th * n excess ^ oes not saccharify the gummy matter dissolved in thej^dy into suo-ar 6 starc ' 1 sugar, but when the gum is insulated, it is convertible almost

oaj*' A Watery , * C ’i Cane su S a !"> an d beer yeast, suffer no change from diastase,j “^contact of aff 1011 ^' astase readily decomposes on keeping, either in contact or

h 0 ! U ^' n itted tf t r h C p h - s U7ur, whether obtained by means of diastase or sulphuric acid,1 c ‘ ( l> and WBt SPIri (- U0US luementation, the sum of the weights of the alcohol, car-r uy about 31 ...'7 0 crystallization of the sugar, is less than the weight of the2 cent. This difference proceeds in a great measure from the form-