CHEMICAL SCIENCE. 183 



heat is uniform, and the expense is said to be less than that of the mode 

 of drying heretofore generally adopted. By Mr. Stafford's apparatus, 1C or 

 17 pounds of water are expelled from each barrel of flour, which reduces the 

 proportion of water to 4 or 5 per cent., an amount too small to be pro- 

 ductive of injury. Absolute dryness cannot be easily attained, except by 

 a long exposure of the flour to the heat, and it is not necessary for its pre- 

 servation, a reduction of the water to a small per-centage answering all 

 purposes." Professor Beck says, " I cannot, in my opinion, render a 

 more important service to dealers in breadstuff's, than to recommend 

 strongly the employment of this or a similar process of drying." 



CARBONATE OF SODA AND BREAD. 



IN a recent letter, Professor Silliman, Jr., advocates the use of car- 

 bonate of soda instead of yeast in making bread. He says, " I 

 have paid some attention to the method of making bread by carbonate 

 of soda and muriatic acid, and have eaten with pleasure of bread so 

 made. The result of the mixture of these materials in the proper pro- 

 portions of flour, is to set at liberty such a quantity of carbonic acid 

 gas as is necessary to thoroughly raise the bread on the instant in the 

 process of baking. The salt formed by the union of the alkali with 

 the acid is just sufficient to flavor the bread pleasantly, and no objec- 

 tion can rest against the process when properly conducted. The or- 

 dinary mode of kneading dough with yeast is vastly more laborious 

 and difficult in every respect than the quick process. The yeast em- 

 ployed in fermentation is objectionable as being a substance far ad- 

 vanced in decomposition, and not always free from an unpleasant acid- 

 ity, which it imparts oftentimes to the bread made from it, although 

 in a degree which may not make it unsaleable. The process of fer- 

 mentation is carried on in the dough at the expense, first, of a certain 

 amount of sugar which is present in all good flour, and when this is 

 all converted into gas, then the starch of the flour is attacked, until 

 the progress of change is arrested by the oven. The loss of weight 

 sustained by the flour in the usual fermentative process is all saved by 

 the quick mode. There is a certain breaking up of the starch globules 

 by the fermentation, and probably also a change in the consistency of 

 the glutinous part of the flour, which makes fermented bread peculiar- 

 ly tender and friable, which is an advantage that may be fully com- 

 pensated in the quick bread by longer baking. I am informed that 

 bread made by the quick process requires a much more considerable 

 time hi the oven than fermented bread." 



STARCH FROM HORSECHESTNUTS. 



M. BELLOE stated to the Paris Academy of Sciences, at their 

 meeting on Jan. 15th, that he had obtained perfectly white and 

 tasteless starch from the horsechestnut, by simple washing in cold wa- 

 ter and decantation. With rough apparatus he obtained from 19 to 21 

 per cent, of starch from the pulp of the fruit, while a comparative ex- 

 periment gave him but about 12 per cent. But on January 22d, M. 



