272 Dk ColquhoutCs Essay [Oct. 



from causes not well understood by the baker, the dough* of 

 gingerbread becomes thus matured and ripe for the oven^ on 

 some occasions much more speeaily than on others; but, in 

 general, if the dough were fired at an earlier period than has 

 just been mentioned, the baked bread would more or less 

 resemble in compactness a piece of wood, in proportion to the 

 time by which its baking had been prematurely hastened. -<. t^»;} 



As the alum could be easily dispensed with by the baker/ 

 without at all materially affecting the rising of his bread in the 

 oven, it was plain that it might be laid altogether out of view in 

 the course of an investigation into the pecuharities of this pro* 

 cess. And indeed that its presence could not have the effect of 

 paralyzing the yeast-fermentation is a matter sufficiently plain 

 from the well-known circumstance, that it is not unfrequently 

 employed in baking common wheat-loaves, to render whiter the 

 colour of inferior flour. It was, therefore, in the action either 

 of the butter, or of the potashes, or of the treacle, or in the 

 combined action of these upon each other, or upon some other 

 ingredient in the flour, that the source of the uncommon results 

 attending the preparation of gingerbread was to be traced. And 

 from the experiments made, it seems to be clearly established, 

 that the mutual action of the potashes and treacle upon each 

 other is, the gasifying principle in the present process of ginger- 

 bread-making. 



In order to ascertain in what this principle is situated, a mass 

 of dough was made ready, from which butter was entirely 

 excluded, but which differed in no other respect from common 

 bakers' gingerbread-dough. After being allowed to stand over 

 the usual time, it was baked in the oven, and, when taken from 

 it, proved to be a well-raised gingerbread-loaf. There were 

 next prepared several pieces of dough, having all the usual 

 ingredients except the carbonate of potash, and it was found, 

 that neither when baked immediately upon being made, nor 

 afterwards at various intervals during several weeks, did the 

 bread come from the oven otherwise than solid and compact, 

 just such as common bread is, the dough of which has never 

 been fermented. In the next place, two portions of dough were 

 prepared, from both of which treacle was excluded ; and in one 

 of them its place was supplied by an equal weight of refined 

 sugar dissolved in a minimum of hot water. But in neither case 

 did the bread return in the least degree porous or vesicular 

 from the oven ; and exactly the same results were obtained, 

 both when the dough was baked immediately after its prepara- 

 tion, and at successive intervals during the lapse of several 

 weeks. From these experiments, the inference seemed to he 

 clear, that the simultaneous presence of the treacle and of tlie'- 

 carbonate of potash, and their mutual action, must be es^eijitiijlj^* 

 to the formation of good elastic gingerbread. / .. 



