From "The London Journal of Arts and Sciences" 1856, paper by Mr. Henry Marten, of Wolverhampton.

A very cheap and effective description of temporary pumping engine for rough colliery purposes, where saving in first cost is a more important object than great economy of fuel, came some time since under the writer's observation at a colliery near Nailsea. The engine was constructed by Mr. Hughes of the Uskside Foundry, Newport, and consists simply of a large open-topped cylinder placed vertically on two cross beams over the pit shaft. The working apparatus consists merely of a steam valve for admitting the steam under the piston, and an eduction valve for letting it out, with a steam-slide throttle valve, and eduction-slide throttle valve, for regulating the rate for the admission and exit of the steam. The two former valves are worked by tappetts, attached direct to the piston-rod: the two latter are adjusted by hand, so as to regulate the number of strokes per minute, - the engine being in fact its own cataract. This engine is remarkable for its simplicity and cheapness of construction, and has now been at work for some years. The consumption of fuel with a good description of boiler is not more than the average of ordinary colliery pumping engines as at present constructed. The general arrangement for a plunger pump would be as described above; with a lift pump it would be necessary to have a balance-bob. Its security is also very considerable, since, if the two throttle valves are properly adjusted, no great damage could occur should one of the other valves stick, as the piston could not travel either up or down faster than the steam could pass through the guarding throttle valve. It is also a portable description of engine, which is sometimes a recommendation in proving mines.

NB: "Mr. Hughes of the Uskside Foundry" is evidently John Hughes of Merthyr Tydfil, who in 1868 formed the New Russia Company to develop coal and iron industries in the Ukraine, and founded the city of Donetsk. A booklet by Susan Edwards, available from the Glamorgan Record Office, gives details of this strange and fascinating story.