I stood with Dr. D. looking from a window upon a group of four or five young men who were engaged in flying a large kite. I was impressed by its great height. "Much as 1,200 feet, isn't it?" I asked D. "More, I should say," he replied, and then he called outside to know how much line they had free. "5,750 feet," they said. I estimated that the cord led upward at an angle of 45 degrees and proceeded to calculate the vertical altitude of the kite, regarding the cord as the hypotenuse of a right isosceles triangle. My result was 4,000 feet, within 65 feet of the precise one (4065 feet).