Week after week, Hal Dane pursued his patient experimenting. He tried two rotors, one above the other and traveling in opposite directions, with the idea of equalizing balance to the nth degree. It did not work; it only complicated matters more. He made shorter, the already short, fixed under-wings, and tipped up their ends. Still the strain was unrelieved, still the mechanism tore to pieces under that whirling force. At last Hal got at the root of the matter--it was too much power hurled down by the gyroscope. By degrees, he learned to decrease the size of the air slots in the gyroscopic instruments, learned to shoot the air stream in a more gradual manner until he achieved just the amount to power the controls, and yet not break them.