Cream butter and sugar. Beat the egg and add to the butter and sugar. Stir baking soda into the boiling water, add molasses, then beat into the creamed mixture.
Sift 5 cups of the flour together with the spices. Add as much of the remaining flour as is necessary to make a good stiff dough, but not too stiff.
Roll out about ¼ inch thick on a lightly floured board and cut into fancy shapes. Place on greased cookie sheets and let chill at least 1 hour, or as long as overnight if you wish.
Bake about 15 minutes in a preheated 375° oven.