This section is from the book "Elements Of The Theory And Practice Of Cookery", by Mary E. Williams. Also available from Amazon: Elements Of The Theory And Practice Of Cookery; A Textbook Of Domestic Science For Use In Schools.
Compare the recipes for Egg Muffins (p. 113), Cottage Pudding, and Standard Cake (p. 277). Cake, you see, is only bread, with more shortening, sweetening, and eggs, in proportion to the flour. Cottage Pudding may be considered either a sweet muffin mixture, or a very plain cake.
Two classes of cakes: butter and sponge cakes. - All cakes belong to one of two classes, butter cakes and cakes without butter, or sponge cakes. Several kinds of cake can easily be made from one recipe, by varying the flavorings, spices, and fruits, by baking the same mixture in pans of different shapes, by frosting the cake or leaving it plain.
In general, a cake should contain not more than one-third to one-half as much butter as sugar, and about half as much liquid as flour. Remember that butter, or other shortening, counts as liquid, since it melts in the oven. Sour milk and molasses do not thin a mixture as much as sweet milk or water. A cake with fruit should be a little stiffer than one without.
Every one who cooks should understand the principles of mixing and raising batters sufficiently to know when she reads a new recipe whether or not it will turn out well, and whether it is extravagant or reasonable.
How much soda is required for one pint of sour milk? (P. 109.) How much baking-powder for one cup of flour? (P. 111.) The more eggs there are in a cake, the less baking-powder is needed.
Account for the absence of baking-powder in Spice Cake and Gingerbread. Why is there no sugar in Gingerbread?
Why does Sponge Cake require no baking-powder? Notice some of the other ways in which recipes differ, and account for these in as many cases as you can. (See suggestions about using fat in cooking, p. 225.)