Thomas Scott Baldwin was engaged in building a dirigible balloon in California when he chanced to see a new motorcycle, the motor of which seemed to be exactly what he wanted to propel his new airship. He learned that it was the design and product of a man named Curtiss, at Hammondsport, N. Y., with whom he entered into correspondence. The result was that Captain Baldwin went to Hammondsport for a personal interview with the man who had turned out the motor. Baldwin expected to find, as he afterward said, a big, important-looking manufacturer, and great was his surprise to find a quiet, unassuming young man, scarcely more than a youth. The jovial Baldwin and the unobtrusive Curtiss became great friends at once. They discussed motors of all sorts, but particularly motors suitable for dirigible balloons, then in the first stage of development. When Baldwin asked Curtiss the price of one of the type then used in the Curtiss motorcycle, he was surprised at its cheapness, and ordered one on the spot. This was built at once and proved successful. Later several other motors were built at the Curtiss factory for Baldwin, each one showing some improvement, and some of them designed to meet the increasing demand for a more powerful motor of light weight for use in dirigible balloons. As a natural consequence of Baldwin's success with the use of the Curtiss motor, it was but a short time until it came to be the best known motor in America for aeronautic work. At the St. Louis World's Fair, in 1904, Captain Baldwin's "California Arrow," the only successful airship out of all those which were brought from Europe and every part of America to contest for big prizes, was equipped with one of Curtiss' motors. Baldwin's success at St. Louis was a triumph for Curtiss, and soon all dirigible balloons operating in this country were driven by Curtiss motors. Hammondsport was now to have a new sensation and to witness an experiment which eventually led to momentous developments. In order to test the power of the motors he was building for Captain Baldwin, and for the purpose of determining the efficiency of his aerial propeller, Curtiss constructed a "wind-wagon," a three-wheel vehicle with the motor and propeller mounted in the rear of the driver. When he took this queer contrivance out on the road for its first trial, the town of Hammondsport turned out to witness the fun. Consternation among the usually mild-eyed work horses spread throughout the little valley as the "wind-wagon" went scooting up and down the dusty roads, creating a fearful racket. Before the start was made an automobile was sent ahead to clear the way and to warn the drivers of other vehicles. The automobile, however, was quickly overhauled, passed, and left far in the rear by the whirring, spluttering, three-wheeled embryonic flying machine. [Illustration: THE BALDWIN ARMY DIRIGIBLE–CURTISS MOTOR] Curtiss at front, at motor; Captain Thomas S. Baldwin at rear