One Thousand Ways to Make Money by Page Fox

401. THE DOUBLE WINDOW.--Here is a plan for window ventilation. It is

the idea of a French physician, but he has not patented it. Have a double window with openings at the bottom of one, and at the top of the opposite one through which the air comes in freely without any one feeling it. The plan is said to possess simplicity, efficiency, and cheapness. Let the American carpenter take notice and profit thereby.