BREAD.

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. first kept moderately hot, by shutting the dampers; hut whenever the thermomelei'ached to it indicates a temperature of from 300° to 290° C. (572° to 554° F.).a j. e dampers or registers are opened, to restore the heat to its original degree, byt , °tving of the circulation of the hot air, which rises from the lower cavities aroundIjJjfireplace into the interior of the oven. When the baking is completed the gas-tal- ’ had fi een withdrawn, is again introduced into the oven, and the bread is

( ■ e a out; called the process of defournement. If the temperature had been main-at about 300 3 C., the 300 kilogs. of dough divided into loaves of one kilog.Hj* 'bs. avoirdupois) will be baked in 27 minutes. The charging having lasted 10JJhtes, and the discharging as long, the baking of each batch will take up 47 minutes.°f c 0n account of accidental interruptions, an hour may be assigned for each chargein -oaves of 1 kilog. each; being at the rate of 6240 kilogs. (or 6-75 tons) of bread~4 hours.

h a 'bough the outer parts of the loaves be exposed to the radiation of the walls,ty^.tcd to 280° or 300° C., and undergo therefore that kind of caramelization (charring)H Produces the color, the taste, and the other special characters of the crust, yetj, er ■oner substance of the loaves, or the crumb, never attains to nearly so high a tem-i rir ,?' tu re; for a thermometer, whose bulb is inserted into the heart of a loaf, does notT^ate more than 100° C. (212° F.)

0ar oc theory of panification (bread-baking) is easy of comprehension. The floura tiv S valuable quality to the gluten, which it contains in greater abundance than°f the other cerealia (kinds of corn). This substance does not constitute, as hadhup fi ere tofore imagined, the membranes of the tissue of the perisperm of the wheat:'he e . n dosed in cells of that tissue under the epidermic coats, even to the centre ofIn this respect the gluten lies in a situation analogous to that of the starch.Mu ? Dlos ' °i" 'b e iuimediate principles of vegetables. The other immediate principlesallPlay a part in panification are particularly the starch and the sugar; and they^Pcrate as follows:—

6 diffusion of the flour through the water, hydrates the starch and dissolves thec 0 j? a, 'j the albumen, and some other soluble matters. The kneading of the dough, byPleting these reactions through a more intimate union, favors also the fermen-Hv °*' the sugar, by bringing its particles into close contact with those of theiu t j ® or yeast; and the drawing out and malaxating the dough softens and stratifies it.di s t°uucing at the same time oxygen to aid the fermentation. The dough, whenof touted and formed into loaves, is kept some time in a gentle warmth, in the foldsby cloth, pans, &c., a circumstance propitious to the development of their volumefr’oj^'J'entation. The dimensions of all the lumps of dough now gradually enlarge,is j 'bp disengagement of carbonic acid in the decomposition of the sugar; which gastl; e ^Prisoned by the glutinous paste. Were these phenomena to continue too long,l>oi n j would become too vesicular; they must, therefore, be stopped at the properMdd s P o agiaess, by placing the loaf lumps in the oven. Though this causes aexpansion of the enclosed gaseous globules, it puts an end to the fermentation,-jJ° their growth ; as also evaporates a portion of the water.

Vlci fi erm entation of a small dose of sugar is, therefore, essential to true bread-It s ' n g > but the quantity actually fermented is so small as to be almost inappreciable.ten!?* 8 probable that in well-made dough the whole carbonic acid that is generated'ute s in it; amounting to one half the volume of the loaf itself at its baking tempera-!W ” r 2l2 °- It thence results that less than one hundredth part of the weight of theit, 18 nil the sugar requisite to produce well-raised bread. What egregious folly wasfo t t ? ref °re, to mount the bakery in Chelsea, twelve years ago, at an expense of 20,000 1.,cv eil 6 Pnrpose of catching the volatile spirits in their escape from the loaves in theas it was vulgarly termed, “ taking the gin out ot the bread!” whereas it wasb but taking the cash out of the pockets of the pseudo-chemical visionaries whoThp ** this metropolis.

'be q ric hness or nutritive powers of sound flour and also of bread are proportional tofor b 0 n, !>tity °fi gluten they contain. It is of great importance to determine this point,Wisi| e ; °fi these objects are of enormous value and consumption; and it may be accom-f1 nn? ost eas ily an d exactly by digesting in a wa.ter-bath, at the temperature of 167°^bitis ^ R rE| ins of bread (or flour) with 1,000 grains of bruised barley-malt, in 5,000* blim’ ° r a little more than half a pint, of water. When this mixture ceases to take'be gi g°lor from iodine (that is, when all the starch is converted into soluble dextrine)v l2 Q left unchanged may be collected on a filter cloth, washed, dried at a heat of''"’bed ■ We %hed. The color, texture, and taste of the gluten, ought also to be ex-Ipa 5 forming a judgment of good flour, or bread.

'lH^i I'endently of the skill of the baker, bread varies in quality according to thewater and gluten it contains. A patent of German or French origin washere a few years ago, for manufacturing loaf-bread by using thin boiled flour-

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