1851 Great Exhibition: Official Catalogue: Class V.: Watkins and Hill
56. WATKINS and HILL, 5 Charing Cross — Manufacturers.
1. Sectional model, to illustrate the construction of a condensing steam-engine. One face showing the whole of the valves and pumps moving at their exact times, and the other presenting an outside view of the engine.
2. Sectional model of a condensing steam-engine, with section of the boiler and furnace. These models are constructed in metal for use in tropical climates.
3. Sectional model to illustrate the construction of the locomotive steam-engine. One face showing the formation of the tubular boiler, and the action of the various working portions, and the other presenting the exterior appearance of the engine.
4. Improved mercurial barometric steam vacuum gauge, combined on the same metal frame and scale, with an atmospheric barometer, to give an accurate comparison of the vacuum and atmospheric pressure.
5. Sectional model to illustrate the construction of the marine steam-engine, without the boiler. One face showing the action of the pumps and valves, the other presenting the exterior appearance of the engine.