Nikola Tesla U.S. Patent 1,061,206 - Turbine Patent Wrapper Page 34

898 efficiency was remarkably high. The rotor was nine and three quarter inches in diameter and two and one half inches long, and was composed of smooth disks mounted upon a shaft with openings near the centers for exhaust. The steam consumption was measured by means of a surface condenser, and an accurate scale was employed to weigh the condensed water for a given period of time. The accompanying photograph which I have marked "Exhibit A" represents a drawing of the 100 HP Tesla turbine above described. The steam was made to enter a nozzle chamber located at the top of the turbine, the nozzle being carried by a rotative member provided with a hand wheel, by means of which the steam was made to impinge on the rotor in opposite tangential directions at will. I witnessed the reversing of the turbine on several occasions. The sectional view in photograph Exhibit A illustrates the construction of the rotor, which was composed of space, plane smooth disks with openings near the center to permit exit of the steam which entered th rotor tanger-i tially and traveled in a free spiral path toward the center, leav ing through the holes above mentioned. The readings of the pressure gages taken during the tests indicated clearly a conversion of heat into mechanical power, taking place partly in ta the nozzle and partly in the free spiral path of the steam through the rotor. I recognize the accompanying drawing marked. "Tesla Reversible Turbine, Nov.30,1908", as a drawing of the 100 HP Tesla turbine described, with the exception, however, that the exhaust was located on the side as shown in photograph hereto annexed and marked "B"and not at the bottom as shown in: photograph A. -333 1