The Forgotten Highway
English Heritage
Notes from archeological Survey taken before the site was demolished for the block of flats
The Greenwich Steam Ferry was opened on 13th February 1888. The engineers were Clark and Standfield, a -
The Ferry had three basic elements -
The power for this operation was provided by stationary steam engines on both sides of the river, located within engine rooms immediately behind the river wall and below the adjacent roadway.' The contemporary account (ibid) records that the traveling carriages were linked by 4-
The steam was supplied by three boilers of locomotive type, reportedly producing up to 140 lb. per square inch although seldom used to capacity. However, with the exception of the some there do not appear to be any detailed contemporary records of the Steam Ferry operation.
The ramp with its four sets of rails is clearly shown, whilst the Engine Room lies immediately to the south (the northeast corner of the present site). One of the carriages is illustrated on wheeled bogies drawn up to the shore. The section also shows one of the two counterweight shafts below the Engine Room floor. Each shaft was nearly 50m deep and about 3m in diameter.
The Steam Ferry did not prove a success -
Sometime after 1914 a single storey building was constructed on the ground above the Engine Room, and there is also a reference to the use of the Room itself as a wartime air raid shelter. More recently the inside face of the riverside wall was heavily reinforced with concrete. This latter has obscured all internal features, and based on the 1892 description of the river wall (ibid) probably extends at least 0.5m over the original floor. However, the approximate positions of the cable ports can still be seen on the external face of the wall.
8.2 The Engine Room -
The Engine Room survived up to the present day and remained a structure of some significance, although not listed or scheduled. In general appearance it formed a single large chamber, devoid 'of in situ machinery but with a number of features indicating its former use. Internal measurements were about 20m by 9m in plan, tapering at the western end to just over 1m. The main standing structure was of solidly mortared yellow stock brick, apparently frogged, over a concrete base. The room was divided into a series of bays east to west by more or less centrally placed iron pillars, supporting beams and a roof of the same material
The Engine Room floor was also constructed at two levels, with the finished surface in the eastern part at about I.80m OD and the western end (slightly less than one-
Although the Engine Room was only in use for about twelve years (1888 to c 1900) some changes may have been made to the operation of the layout: for example, it is known that the Ferry was suspended in the early 1890s.
The following sections describe the Engine Room in more detail, and broadly in terms of its constituent elements from the base up -
8.2.1 The foundation
The Engine Room was founded on a continuous slab of concrete, which during development works was broken -
Although not reinforced the slab was generally very solid. The concrete mix was fairly coarse but homogeneous, with medium flint gravel aggregate plus scattered larger flints and brick rubble in a few areas. There was a finer surface screed (c 40-
Deposits immediately below the slab (with the exception of the earlier drain varied from a 'foreshore' type material of mixed gritty or sandy silt with a few fragments of shell and ceramic building material to a solid grey-
The main slab was therefore constructed as a raft over alluvial deposits, and did not {except probably to the north below the river wall) make contact with the underlying River Terrace gravel. This latter deposit was exposed during excavation of the earlier 19th century drain {cf section 7.), its surface recorded just over 1m below the base of the concrete slab {c-
8.2.2 Ground floor layout and features
The differing floor levels in the Engine Room reflect the two basic elements of steam power: the lower Western -
The Boilers
Although defined Iv the general layout of the Engine Room, the position of the boilers is: also reflected in two sets of discrete features:
At floor level in the southern side there were three circular features within the concrete. The Western of these was heavily disturbed and the eastern had been partly removed by a small drain that probably postdates the operation of the Engine Room. However, the centre feature survived as an unbroken circular trough, just over 1m in external diameter and about 100mm wide by 60mm deep.
It seems clear that these mark the positions of supporting rings for one end of each of the three recorded locomotive-
. Within the adjacent southern wall and in line with the above features were three circular shafts, each 1.3m in diameter and between 1.06m and 1.66m deep. The shaft linings had been prefabricated from iron plate riveted together to form sides and end, and then built into the waft during construction.
It is assumed that the shafts were to give access to the smoke box and tubes at the front end of each of the boilers. It is not known whether the markedly shallower depth of the western shaft indicates a different (?smaller) boiler.
There was no evidence for coal storage within the boiler area (or elsewhere in the Engine Room), although it is possible that there were one or more bunkers set against the now-
A few other features in the boiler area are worth noting, although not fully understood. One of these was metal shelf some 460mm square that was attached to the base of the westernmost roof pillar, some 0.6m above floor level. The western end wall also exhibited some evidence-
The Engines
The upper floor area retained considerable evidence for the siting of machinery, including a central flywheel pit and a series of symmetrical features to the east and west that presumably relate to the coupled engines that moved the traveling carriages. The features included further wheel pits, a considerable number of bolts and rebates up to 250mm deep set into the floor surface, and various pipes and channels.
The dimensions of the central flywheel pit (2.3m long by 0.8m deep) suggest that the wheel itself was up to 2.2m (just over 7 feet) in diameter: it is evidently this feature, partially obscured; it can be seen in the contemporary cross-
The various pipes in the Engine Room floor included two of 25mm (1 inch) internal diameter, which had been laid around three sides of the presumed engine bases. Each pipe had six junctions (three to the east and three to the west) to take vertical feeders from the engines themselves, and then ran northwards apparently to discharge into one of the counterweight shafts. Elsewhere to the east there is evidence for other equipment, including several features with adjacent pipe channels that may have supported tanks. The circular impression in the southeast comer included a central hollow with a residue of heavy oil, which perhaps indicates storage of this material.
Evidence for the separate two-
Above floor level there was limited evidence for the operation of the Engine Room, notably the two sets of brackets attached to the each of the central roof pillars. These were identical and both south-
The shafts
At floor level within the northern part of the main Engine Room there were three shafts (Fig 9). The larger of these, to east and west, are readily identifiable as the counterweight shafts that -
The contemporary description gives the depth of both counterweight shafts at over 145 feet (44.2m) below the roadway (The Engineer 1892, 487). In recent years the eastern shaft has been dived and subsequently plumbed to the same depth from within the Engine Room -
The counterweight shafts were of similar although not identical construction. Both were lined by a series of -
At floor level there was one further slight contrast between the shafts. To the east the -
Following excavation of the floor slab around the western counterweight shaft a more significant feature came to light. The smaller iron ring (and that directly below) were set within a larger ring, apparently identical to those used in the eastern shaft (Figs 16 & 17). The reason for this is unknown, although it may be noted that the -
Between the two counterweight shafts was a smaller and quite different shaft, some I.84m (6 feet) in overall diameter. This was recorded in plan and subsequently during reduction of the adjoining slab to a depth of about 0.9m. The interior remained full of water but was plumbed to a depth of about 5.8m.
The shaft lining was constructed from iron plate formed to a cylinder and close-
The purpose of this third shaft is unknown although it may well have supplied the fairly large quantities of water that would have been required by the boilers. In Operation this might not be easily obtained from the counterweight shafts, whilst the tidal and sometimes muddy river would not be an attractive source.