The number of successful glides accomplished by Mr. Wilbur Wright and his brother, with their double-decked gliding machine in America, would seem to be a proof of the value of those careful preliminary experiments which it has been the custom of these intrepid aviators to originate. After their first experiments, made with gliding machines in 1900 and 1901, they undertook laboratory experiments for the purpose of determining the amount and direction of the pressures produced by the wind upon plane and arched surfaces exposed at various angles of incidence; upon the results of these experiments a new pattern machine was constructed in 1902.