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.
Dough means "that which is moistened"; batter means "that which is beaten."
One measure of liquid to two measures or a little more of flour makes a thick or drop-batter.
A mixture stiff enough to be handled on a board is a dough.
One measure of liquid to two and two-thirds measures of flour makes a soft dough.
One measure of liquid to three or more measures of flour makes a stiff dough.
A mixture of flour and water or flour and milk alone would be, when cooked, hard and unpalatable. We have found that the introduction of carbon dioxide makes it light and porous, and that, in a watery batter cooked by intense heat, the steam produced puffs the batter up. Eggs stiffen batters. (See Muffin Recipes.) With very glutinous flour (pp. 116 and 120) eggs are unnecessary except to make the bread richer. Fat shortens bread; i.e., makes it more tender by separating the starch-grains of the flour. Butter gives a fine flavor; but less expensive kinds of shortening may often be used. (See p. 225.)