The following text is from the original listed building designation:
TQ 66 NE COBHAM COBHAM PARK
4/10004 The Engine House,
Cobham Hall
II
Horse-powered engine house. Erected in 1789 by Samuel Lapidge. Red brick in irregular bond with Roman cement features. Octagonal structure with square engine house to rear. The octagonal structure originally housed a horse-powered pump. Roof missing at time of survey. Roman cement parapet, cornice and buttresses. Square part has arched entrance and lancet windows to the sides. Octagonal part has some lancets. At the time of survey there was a large gash in the brickwork. An exceptionally rare building because of its early date for a pump house and use of horse power.
Listing NGR: TQ6797468916
(1)

A plain circular building of red brick, built in 1789-90, taking over the function of the mid-Seventeenth century Fountain House. The circular chamber contained a Joseph Bramah horse engine. By 1804 it was improved with a higher roof and a Gothic octagonal upper storey in order to enhance its appearance. It was in ruins by 1969. (2-3)

There may have been an internal gallery around the upper storey. The hall was connected to the mains water supply in 1906 and the machinery of the pump house removed in 1932. The building was damaged when a tree fell upon it. (4)

<1> English Heritage, List of Buildings of Special Architectural or Historic Interest (Map). SKE16160.

<2> English Heritage, 2002, Historical Account, Cobham Hall Estate, Part 2: The Gardens and Inner Grounds (Unpublished document). SKE17515.

<3> J.E.L. Caiger, 1969, The Pumphouse on Cobham Hall Estate (Article in serial). SKE17516.

<4> Alan Ward, 2008, Building recording undertaken in the North Pleasure Grounds and Lady Darnley's Garden, Cobham Hall, Kent (Unpublished document). SKE17814.