Combine water and milk; stir well, and chill thoroughly.
Combine flour, baking powder, sugar, and salt; stir well. Cut in shortening using a pastry blender until mixture resembles coarse meal. Add milk mixture, and stir with a fork until dry ingredients are moistened. Shape dough into a ball, and chill.
Press chilled dough through a bread brake until air bubbles form. Repeat procedure for 30 minutes, folding dough each time to incorporate air between the layers.
Roll dough to 1/2-inch thickness; cut with a 1 3/4-inch biscuit cutter. Place biscuits on lightly greased baking sheets. Prick biscuits with the tines of a fork, and brush with melted butter. Bake at 350° for 30 minutes.