1895 Patent No. 9404 balanced piston valve, Smith Hart & Wilkinson, Johnston, Pa

Patent No. 9404 A.D.1895 Improved Balanced Piston Valve

"We, John Adam Smith, James Hart, and Abraham Wilkinson, all of No. 305 McConaughy Street, Johnstown, Pa., U.S.A., Inventors, do hereby declare the nature of this invention to be as follows: This invention relates to steam hydraulic, and similar valves of the class known as balanced valves, and the objects in view are to provide a piston-valve in which the pressure of the fluid prevents the packing rings from expanding into the moving part or piston..."

3 pages of text + 1 drawing which have been disbound from a larger volume.

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