Literally on the back of an envelope. The front of the envelope is here: Boston Cookies.
From the box of S.H. of Marshall, Missouri.
Butter Scotch Cookies
1 cup butter
4 cups brown sugar
4 eggs
1 tsp. cream of tartar
1 tsp. baking soda
6 1/2 cups flour
Cream butter and sugar. Add well-beaten eggs. Add flour, sifted with rest of dry ingredients. Make in loaf; let stand overnight. Slice thin and bake, 350 deg. oven, 8 minutes.