Archaeological investigation
Season 2
Investigating the ENGINE HOUSE
Berengrave Local Nature Reserve
Map reference TQ821672
The range pole used in all photographs is 1m overall
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The Site was reopened on 15thSeptember, 2009
After a meeting with council officers a program was agreed and skips were ordered so that rubble could be removed.
Two new members Dave Chalk and Doug Chidley were introduced to the dig so, with Ed Newport, Brian Baker and Fraser Miller we have improved the investigation team. The skips were delivered and the barrowing began, this took about five hours and in the end the rubble from the engine house and the wash mills along with all the old tree branches in the mills was removed. This should help reduce the vandalism. Unfortunately four of the notice boards provided by FoB have recently been vandalised and reduced to scrap. They have been removed by the Rangers and will not be replaced.
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Dave Chalk.
Is this a smile or grimace?
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Fraser Miller (and helper) with the last barrow full ....
.... for the time being.
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Engine House layout
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| The area below the steps is sloped to the north as the boiler locating pin is located on a raised plinth. The other pin is almost flush with the floor. |
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| The feature to the east of the narrow set of steps comprises of a depression approx 700 mm wide with a wooden block embedded in the floor. The depression then extends to the east and is in line with the flat face of the U section iron uprights |
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When the area around the engine house was cleared there was a 2.5m drop very close to the path.
The safety barrier fitted was fitted on 2nd Oct. 2009
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From the fill layer of area EN some fragments of the wall cladding were found. These were painted on one side and suggest the engine room was painted white with red wood work.
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Also found in the same area was the cast-iron pipe support along with about 20 assorted bolts.
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The same item but showing the broken off end to the right and the central fixing hole along with the clamping bolt holes.
This is yet another item without a makers name.
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The entrance to feature EN has a length of 150mm square timber fixed to each side. These timbers have lost approx 300mm from their tops due to natural decay. The area between the wall contains a mixture of chalk rubble and a clay type soil, this mix has been found in the area outside the wall ends and we are unsure where this mix originated as it appears out of character with the process of the site.
The fill material in the south east corner is a mix of chalk nodules, a few asbestos shards but mainly the clay material. In the very corner a collection of bolts some with nuts was recovered along with a length of heavy iron bar approx 600mm x 75mm with a series of holes at one end. At the level of the water which is approx 300mm above final floor a cast iron saddle was recovered. This item has been a double but is broken in half it would accommodate a pair of 200mm O.D. pipes. Perhaps this was the type of support used for the pipes to transfer the slurry to the cement works.This support has a central fixing bolt and two clamping holes at each end.
In mid September, 2009, the engine house began to refill with water as the water table rose. Work then moved to the north of the brick piers and, as expected, found this area to be mainly brick rubble to a depth of approx 600mm then a layer of rich loam was found along with the remains of a die-cast model of a six wheel lorry. This confirms what we were told earlier that the slurry tank was approx 600mm high until the 1960s when it was cut to ground level to allow lorries to pass when the chalk pit was to be used for land fill. This loam layer was presumably the result of years of detritus build up.
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At the eastern end of the boiler house a wooden hand rail was recovered, this item was the correct length to link a pair of sockets one at the top of the wide steps the other located on the last step against the side of block EQ.
The picture on the left is computer generated to show the position of the handrail
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This is a spring steel pipe clamp recovered near floor level close to EN and is the first of this type to be found
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A trial trench was cut through between the two boiler mounting studs. This trench runs east to west and terminated against the eastern wall. Although the water was approx 150mm deep over the main floor at about 300mm from the wall I believe I detected a channel running along the base of the wall. In this trench I recovered what I think is a filter/strainer, this item was the last thing recovered before shutting down this part of the dig.
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The strainer
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The strainer is constructed from heave gauge wire, mounted into a heavy metal ring into which are fitted two threaded studs, one of which has retained its circular nut.
The area in the north east corner has several layers of corrugated iron sheeting lying almost at floor level and upon investigation it was found to be supported on the fourth and final boiler stud. This iron is still covered by some of the brick rubble in the corner of the site. By this time the rising water level in the engine house was making the rubble very heavy to lift out and remove to the dump area. Work had to be stopped until the spring when the engine house could be pumped out. The site was put on stop in March 2010 on the grounds of Health & Safety because of the amount of water held in the engine house pit.
A meeting with the council in july, 2010, when it was pointed out that after a full clearance had been done we intended to back-fill with rubble and larger pieces of tree stumps and branches in order to create an amphibian pond which could not be fished, permission was given for us to continue with our investigations into this feature.
The engine house pit was pumped out on 26th July, 2010, revealing the wooden battens and corrugated iron sheets which had caused the stop as the water rose.
The wooden batons turned out to be a door with its hinges in place. This comprised of four planks with two cross braces. Unfortunately the metal fixings had all corroded away and the door was recovered in pieces. The wood is in good condition due to being submerged in water since its burial.
After having been photographed, the door was laid on top of the boiler stud block then covered prior to the area being backfilled.
Below the door was the sump located the previous autumn and which turned out to be larger than expected
The engine house floor is divided into two areas. The first is the boiler mountings, which comprise of a 'H' section concrete form with mounting studs at the four corners of the 'H'. The second is defined by two 'U' section uprights connected at their bases with heavy iron bar and heavy angle iron which is embedded into the edge of the 'H' boiler mount concrete. This structure and the iron mounting plate embedded into the wall has been made to hold a piece of machinery, possibly the steam engine.
The picture shows the 'H' shaped boiler stud mounting block. The edge nearest has had the floor blended into a flat surface between two studs and the other half of the 'H' is approximately 300mm deep, allowing the floor to drain away from the steps end of the building. This space has a thick deposit of fine chalk slurry against the concrete. The pipe is also partly blocked with hard chalk deposits.
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The cast-iron pipe which emerges from the base of the east wall. This pipe is situated almost at floor level and is centered on the H mounting block.
The depth of the pipe means it could pass under the adjacent slurry tank (feature EO). No trace of this pipe was found in the half of the slurry tank which was excavated last year. Also, as the slurry tank is now full of rain water, if the pipe had been connected to it, it would have been reasonable to expect water to drain into the boiler house sump,
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The pipe emerging from the wall of the boiler house with north brickwork of feature EN at the top of the picture.
The pipe is a flanged 7in bore with seven bolt holes. There is also a rubber sealing gasket in place.
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Apart from some more rubber gaskets ranging from 7in bore and seven bolts, a 6in bore with four studs and an unusual 2-1/2 in bore with four studs which have 4in centers on three sides, resulting in an odd 2in center between the last two, and some more of the heave rubber seal rings, no other artifacts were found in this part of the sump.
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The final strip to be cleared was the area between the short steps, the south wall of the boiler house and feature EN. In common with the other side. this floor slopes from the base of the steps to feature EN. Apart from two flat bars similar to harrow blades but with a different set of holes nothing else was recorded. The fill layer comprised of asbestos shards on top of a layer of chalk nodules which lay on top of a black layer which gave off a strong smell of oil and left traces of oil on the water.
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This picture shows the South edge of the H block with two of the studs, the two U section uprights, the mountings embedded into the boiler house wall and feature EN with the lower parts of the timber uprights and threshold.
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Feature EN is constructed of yellow stocks with the rear wall smooth cement coated. As the rest of the boiler house sump is finished is this manner it appears the two brick piers were added later and not coated. The timber set into the edges is 4in x 3in and has a similar piece across the threshold. Behind this bar there is a layer of fine chalk slurry covering the concrete floor which is the same level as the main floor. On top of the layer is a layer of fine granular chalk then demolition material. Above this as already recorded was a mix of chalk nodules and clay which I can only assume is hill wash. This may account for the tops of the uprights having rotted off if they were exposed for a number of years before this area was finally filled when the holding tank EO was demolished.
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The final clearance was done on 10th August 2010 after which the area was back-filled with rubble and heavy tree trunk and root systems which were littering the site. During the next winter rainwater will fill the tank which should provide an ideal habitat for amphibians.
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This ended the investigation into the engine house
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Fraser Miller
Archaeologist
Friends of Berengrave
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