Preheat oven to 425~. In a food processor or a large bowl,mix the flour with the salt,sugar and baking powder.Cut the shortening into the dry ingredients until the mixture is the texture of cornmeal. Seperately mix the egg with the milk,and stir all but 2 tbs. of this liquid into the dry mixture. Mix just enough to make a uniformly moistened dough. Drop spoonfuls of the dough onto a greased and cornmeal coated cookie sheet about 1" apart. Brush tops with reserved liquid.Bake in the preheated oven until puffed and brown,about 12 minutes. Cool for a few minutes before serving. Yields about 15 biscuits.