====== Patent XC-12: 1830-06-25, Improved hydraulic steam engine ======

^ X Number      ^ Date       ^ Inventor       ^ City             ^ Title  ^
| XC-12       | 1830-06-25 | Robert Hoyle | Lacolle, QC Canada | Improved hydraulic steam engine |

===== Comments =====

The inventor was "of the seigniory of Lacolle, in the district of Montreal". XC patents are Canadian patents issued between 1824 and 1869. Scans of the drawings are not available. The specification is summarized below.
"The Engine is composed of two or more wooden cylinders or vessels bound together of sufficient strength, and placed perpendicularly in or near a reservoir, of the same depth as the length of the cylinders or vessels, that they may fill without the aid of a vacuum. In each of these cylinders is placed a float of wood or other buoyant material that is a slow conductor of heat, closely fitted without touching the sides, to separate the steam from the surface of the water, and thereby prevent its condensation; guides are made use of to keep the floats steady; suitable valves are placed in or near the bottom of each cylinder or vessel, in order to prevent the free ingress or egress of the water. A steam chest with its valve or valves, is placed on the tops of the cylinders or vessels, to admit the steam from the boilers into them, and permit it to escape alternately. The action of the engine resembles that of the common single forcing pump, (the steam acting as a piston immersed in the water the length of the piston stroke.) The improvement in the Hydraulic Steam Engine, thus made, consists in the use of wood or other non-conducting materials in the construction of the vessels or cylinders and floats, as above described, and in lining with the same material, iron or other metallic vessels or cylinders, for the alternate reception and discharge of steam and water employed in this form of Engine."

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