Nikola Tesla U.S. Patent 511,916 - Electric Generator Patent Wrapper Page 23

30 9 Substitute а Trov. 4, 7/93 under ordinary working conditions that such control may be entirely adequate to produce the desired results. Having now described my in venti on what I claim is: 1. The combination with the piston or equivalent element of an engine which is free to reciprocate under the action thereon of steam or a gas under pressure, of the moving conductor or element of an electric generator in direct mechanical connection therewith. 2. The combination with the piston or equivalent element of an engine which is free to reciprocate under the action of steam or a ges under pressure, of the moving conductor or element of an electric generator in direct mechanical connection therewith, the engine and generator being adapted by their relative adjustment with respect to period to produce currents of constant period, as set forth. 3. The combination with an engine comprising a piston free to reciprocate under the action of steam or a gas under pressure, and an electric generator composed of field magnets or coils and a core or conductor capable of oscill at ion in the field produced thereby, the said core or conductor being carried by the piston rod of the engine. as set forth. 4. The combination with an engine operated by st eam or a gas under pressure and having a constant per-14