The Chanute glider weighed 23 pounds, spread 135 square feet, and readily carried a total weight of 178 pounds at 23 miles an hour. It was provided, as shown, with side planes and a double rudder, and this latter was elastically connected to the main body to insure steadiness of flight, on the principle of the elastic wing margins used by D. S. Brown in 1874. This craft was found easy to manipulate in launching, sailing and landing, a two-inch shift of the pilot’s weight equivalencing a five-inch shift on the Lilienthal monoplane. It was steady at a speed of twenty to forty miles an hour through the air, even when the wind was blowing seventeen miles an hour overground. The angle of descent was 7.5° to 11°, depending on the speed and trend of the wind. The work of gravity expended in maintaining steady flight was at the rate of two horse power for the 178 pounds, a good showing with the rider vertical. Summer passed before Mr. Chanute could perfect the invention for automatic stability by means of swerving wings; but otherwise the gliding experiments were very satisfactory. The strong and simple biplane evolved during those few weeks of fruitful study, though not an original creation, having been foreshadowed theoretically and experimentally, in the work of Wenham,[30] Stringfellow, Lilienthal, Phillips, and Hargrave, was nevertheless an important contribution to the science of aviation, by reason of its strength and simplicity of design, its efficiency, its stability, and, best of all for that day, its record for good flights and safety. All who could appreciate it understood that the addition of a light motor would transform it to a dynamic flyer, navigable at least in mild weather. The most eager, perhaps, was Mr. Herring; for he had not only mastered this glider, but some years previously had flown successfully rubber-driven models very much resembling it in design. These two aviators, therefore, came to a parting of the ways, Chanute still pursuing automatic stability, Herring impatiently heading for dynamic flight by the shortest route available. Had they continued together on a practical course, they might, ere the close of the century, have anticipated at least the early flights of the French aviators, if they could have constructed or purchased an adequate motor. After some further development of the aërial glider to adapt it to power flight, Mr. Herring began the construction of a dynamic aëroplane. He had previously built very light steam and gasoline engines,[31] and deemed the latter best for a perfected flyer, though preferring steam or compressed air in a first experimental test.