576 Dr, Colquhoun's Essay [Oct. 



larger quantity of the alkaline carbonate than is strictly neces- 

 sary to neutralize the acid. But the shortest and simplest mode 

 of explaining how this process is found to work, will be to quote 

 an example of its use : the following statement is therefore 

 submitted, of the mode of preparing what will be found in prac- 

 tice to be a very good dough, particularly for that kind of thin 

 gingerbread, well-known under the name of parliament cakes. 



1 ake a pound of flour, a quarter of an ounce of carbonate of 

 magnesia, and one-eighth of an ounce of tartaric acid : let the 

 butter, treacle, and aromatic ingredients, be added in the same 

 manner as at present. The use of alum will not be found of 

 any advantage, and will be better dispensed with ; as it is in 

 itself an unwholesome substance, and any good effects which it 

 can produce are in all probability completely supplied by the 

 tartaric acid. It is necessary that the alkali employed, the 

 magnesia, should be uniformly diffused throughout the whole 

 mass of the dough, an object which will be always best effected 

 by intermixing it, bruised to an impalpable powder, with the 

 flour, previously to the addition of any other ingredient. After 

 these have been well mingled, dissolve the tartaric acid in a 

 small quantity of water, and, having melted the butter, pour 

 it, the treacle, and the acid solution, into the mixture of flour 

 and magnesia. Let the whole be incorporated into a mass of 



.dough by kneading, and then set aside the dough, for a period 

 varying from half an hour to an hour. It is then fit for being 

 baked into bread. The delay of at least half an hour has the 

 practical benefit of giving full time for the acid to act upon the 

 alkaline carbonate, so as to render the dough loose and short, 

 or, as a baker would say, to bring it into a state of strong 



, fermentation. The dough prepared in this manner, should never 

 be kept longer than two or three hours before being put into 

 the oven, from which it will in due time be obtained, in the 

 state of a hght, spongy, pleasant bread. 



By the method now proposed, not only is the delay avoided 

 which is so inconvenient in the system at present practised, but 

 there is no unpleasant flavour discernible even when the bread is 

 not at all confected with sugar or spices, and there is no ingre- 

 dient in it at all injurious to the most delicate constitution. 

 The expense of making gingerbread in the manner above stated 

 is a trifle greater than that in which carbonate of potash is 

 employed. The difference, however, is so extremely small, as 

 scarcely to make any sensible addition to the price of even the 

 most ordinary kinds of gingerbread.* 



• Tartaric acid may now be purchased at 4s, 6//., and carbonate of magnesia at 

 Is. 4rf. per pound: it is obvious, therefore, that the cost of the quantity of tl^esp materials 

 necessary to convert seven pounds of flour into gingerbread, will amount to pply 

 »bout5(i. 



I find a good gingerbread, li^iicb proves extremely agreeable to the palate, tQtbe 



