• 1886 - A section of an Illustrated Catalogue of Direct Acting Centrifugal Pumping Engines designed, patented and manufactured by W. H. Allen & Co., at their York Street Works, Lambeth, London, S.E. published in May 1886. [727] [728] [MERL Ref : TR SCM P2/B27] [20190803]

The two engines for Penarth Dock were designated as M40 (Medium lift with 40 inch diameter inlet pipe) a specification which is not shown within the above list so was probably a 'special' for the application. The range of outputs for the M36 and M42 models, however, suggest that the output at the head, or lift, of 2,000,000 gallons per hour, as specified by Samuel Thomas within his article would satisfy the following estimation of discharge rate : 2,000,000 / 60 x 2 = 16,667 gallons per minute per pump nominal output. This value seems to be a conservative estimation for the size of pumping engine but is probably realistic given the extremes of tidal rise and fall experienced in the River Ely and in consideration of the differences between available depth of water at spring in comparison to neap tides etc.

The Discharge pipe was orientated in position 'F' whereas the Suction pipe was also vertically downwards i.e 'C'.