Popovers

Source: 1907 Pure Food Cookbook
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Into a bowl, put 1 cup of flour and one-fourth level teaspoon salt, add gradually 1 cup of milk, drop in 1 unbeaten egg. Beat gently at first, then vigorously until full of bubbles. Turn into hot greased gem pans or stone cups, and bake in a moderate oven, that the air in the dough may have time to raise the batter before a hard crust is formed. Bake slowly, at least forty minutes and do not remove before they are dry and firm to the touch, or they will fall. They should double in size.