Flight.
In 1887 the late Professor S. P. Langley of Washington began experiments in mechanical flight. He found that one horse-power will support in calm air and propel at forty-five miles an hour a wing-plane weighing 209 pounds. Dr. A. F. Zahm, of the Catholic University of America, at Washington, has recently ascertained that a thin foot-square gliding plane weighing one pound soars with the least expenditure of power at about 40 miles an hour, while at 80 miles the power required is more than twice as much. As engines have been made weighing less than ten pounds per horse-power, capable of yielding a horse-power for five hours with four pounds of oil, we are plainly approaching the mastery of the air,—so freely exercised by the sparrow and the midge. Among the students eager in this advance are the men who examine with the camera how wings of diverse types behave in flight, and then endeavor to imitate the strongest and swiftest of these wings.