text: The first accumulators for William Armstrongs hydraulic dock machinery were simple raised water towers. Water was pumped to a tank at the top of these towers by steam pumps. When dock machinery required hydraulic power, the hydrostatic head of the waters height above ground provided the necessary pressure.
  These simple accumulators were extremely tall. For instance, Grimsby Dock Tower, built in 1852, is  tall. Because of their size, they were costly, and so were constructed for less than a decade. Around the same time, John Fowler was working on the construction of the ferry quay at nearby New Holland but could not use similar hydraulic power as the poor ground conditions did not permit a tall accumulator tower to be built. By the time Grimsby was opened, it was already obsolete as Armstrong had developed the more complex, but much smaller, weighted accumulator for use at New Holland. In 1892 the original Grimsby towers function was replaced, on Fowlers advice, by a smaller weighted accumulator on an adjacent dock, although the tower remains to this day as a well-known landmark.
  Other surviving towers include one adjacent to East Float in Birkenhead, England, and another located at the Bramley-Moore Dock, Liverpool, England. The latter tower is to be renovated as part of plans for the proposed development of the area associated with the construction of a new football stadium for Everton F.C.