Heat molasses in small saucepan to boiling point. The boil 1 minute. Add sugar and butter and stir until butter is melted. Cool. Beat in egg. Sift together flour, salt, soda and spices. Add to first mixture and mix thoroughly.
Cover bowl tightly and chill overnight. Roll out a portion of the dough at a time on lightly floured pastry cloth. Roll out thin. Cut into desired shapes. Bake in a moderate oven (350) 6 to 8 minutes. Makes 10 dozen cookies.