Archaeological investigation
Season 2
Investigating THE ASH MOUND
Berengrave Local Nature Reserve
Map Reference TQ 821672



The range pole used in all photographs is 1m overall

 

This area is the mound outside the north wall of the boiler house and lies between the concrete floor surrounding block R and the poor concrete floor at the base of the coal chute. It was in the extreme eastern end of this area that the fragment of pottery with the Saint George's Union logo on it was found.

The mound is approx 600mm deep in the centre and is constructed from ash. A cut through the centre revealed a large iron plate with a series of holes around the edges. This plate had been deposited on top of approx 200mm of ash with a further 150mm of ash covering it. The final 150mm is formed from detritus and not from hill wash. This area is believed to have been the ash dump from the boiler house and may contain interesting items discarded during the working life of the site.

The upper ash layer

ash-upper.jpg

ash-lower.jpg

The lower ash layer

The area was opened along side the eastern edge of the poor concrete floor and a trench 1m wide and 1.5m deep cut into the ash mound. The first 100mm, in common with the rest of this area, comprised of detritus heavily bound with ivy roots.

 

After removal of the detritus a layer of ash covered the whole cut to a depth of approx 100mm. Below the detritus a few small fragments of the wall cladding were found, this being consistent with the demolition of the main building.

 

In the next layer some fine white pottery shards were found which were thought to be out of context. In the same fill was a selection of copper wire off-cuts of two different gauges.

shards.jpg

Pottery shards

Below the ash a thin layer of chalk approx 25mm thick lay on top of another thin layer of ash, followed by a layer approx 25mm thick of dirty chalk which is lying on the bed-chalk.

 

The bed-chalk had been cut back approx 150mm to permit a concrete foundation strip to be laid, which supports the north wall of the building.

 

At a later date the western edge of the trench had been cut down through the upper layers to base presumably when the poor floor was constructed in the north west corner of the building. This trench contains a concrete pad with a rectangular hole in it and, further to the north, a steel pin has been driven into the chalk. Lying on the base of this trench is a broken and bent harrow blade, but this has been modified by enlarging one of the holes from 25mm (1in) to 45mm (1-3/4in)

harrowblade-modified.jpg

Modified harrow blade
 

steelplate.jpg

 

The steel plate area was the next area to be uncovered and this revealed the full length and width of the plate, which was 2540mm (100in) by 1370mm (54in) with a thickness of 6mm (1/4in), with a series of 10mm (3/8in) holes round the edges.

The trench along the western edge of the plate was extended to the North until the base of the spoil mound was reached . The ash continued to the north but it was considered that removal of this area would be futile in view of the lack of artifacts. The pieces already found comprise of items already listed along with a length of iron bar with two bolts and a threaded iron ring 5in (125mm) O.D. with a fine thread 4in. (100mm) I.D. and a thickness of 1-1/8 in (30mm), which may be a pipe connector union.

Cut 2. The trench then turns to the east shown as Cut 2 on the site plan, and runs in this direction towards block R and is approx 750mm wide and excavated into the ash layer approx 200mm. It was noticed that the mound slopes downwards and follows the contour line down to an edge similar to layers of hill-wash. The upper layer has a band of red ash instead of the usual grey.  This is the lines shown almost in the centre of the iron plate.

The lower strata edge marks the beginning of the drop into the area listed as Gulley.  This feature is visible heading towards the north and was filled with tree pruning’s which had to be cleared.

Cut 3 extends across to the concrete floor which has the iron pipe embedded and presumably marks the edge of a building. This cut comprises for the first 750mm of ash before giving way to a mixture of clay, chalk rubble and flints. This material is the same as that which has been deposited next to the path and over the other poor concrete floor.

This material appears to have been deposited a long time after the site was closed, which would suggest the gulley was partly clear during the period from 1934 until approx 1960s.

The gulley was cleared to a depth of approx 300mm before ground water began to fill the cut.

Cut 4 started against the wall of the engine house and worked north towards cut 3. This produced some small fragments of pottery and a clay bottle which had been damaged when the safety barrier had been installed. This bottle had no markings. This is also the area where the St. George's Union fragments were found.

 

 

 

This bottle is 120mm high and 60mm dia.

Both inside and out are glazed.

   

The remains of a pot or mug showing the logo used by the St. George's Union of Fulham Road London. This was a work house or poor house until 1913 when it was amalgamated with other institutes into The City of Westminster Poor Union.

The area was cut down to the chalk layer and two holes were found. The right hand one was approx 400mm long 200mm wide and 200mm deep, this is the water level, and does not connect to any thing. The hole on the left hand however extends northwards ultimately opening out to the full width of the gulley.

At the widest point where Cut 3 and Cut 4 join a shaped concrete block shown as Block A was located.

Next to this block two broken casting were found. They are of the same type and are a circular pipe clamp with two drilled lugs on one edge and at right angles to the axis is a square connection. On one of the pieces there is a fixing which seems to have been hinged. The other half has the stubs of small lugs in the same location but in this piece there is no evidence of any fixings left. The bore of the circular pipe is 4in (100mm) and the square holes in the sides are 2-1/2 in x 2in (63mm x 50mm). If both of these castings were once one unit there must therefore have been four clamping bolts but only two bolt lugs on each piece remain. A common feature on both pieces is blobs of lead adhering to the inside of the bore which suggests the addition of a third piece which was soldered in.

   

Arrows show lead deposits

The  picture shows both the castings. The top one shows the complete square hole, the hinge bracket on the top and the two blobs of lead in the bore.




In the other half the square hole is missing but this piece also has lead blobs in the base of the bore.

 

This picture has the complete square hole on the left and the lead deposits in the bottom of the bore with the green tie wire passed through the 3/8in dia. bolt holes.

The concrete block these castings was found next to is embedded in the ash and does not appear to be bonded to the base chalk.

If this gulley did carry the slurry pipes the first or right-hand cut may have been started in error because the pipes would have to run parallel.

The area immediately outside the north wall of the building was excavated down to natural chalk level and showed the concrete post supports which were put in before the strip of concrete wall support was inserted. This wall support was still wet when the timber walling was erected as the imprint remains, and allows us to know the width of timber used.

An area around the 9in x 3in centre roof support has an additional concrete surround, which is shown on the site plan as a shaded area. This material continues to the east before it turns to the north. The rest of the wall support is missing due to the large gap in the engine house wall. It is uncertain if this flooring carried another piece of equipment, but what remains eventually ends in a concrete turn which then blends into the base chalk. Any equipment fastened to this floor must have headed into the gulley and upon its removal resulted in the breaking down of the engine house brickwork and the base of the wall support. The concrete floor is approx 50mm (2in) thick at this point and has been laid on the natural chalk bed.

    

The strata layers at the eastern edge of cut 2.

The water is in the gulley

   

The red ash layer shown.

The range pole is lying on the concrete floor with the rounded end to right of centre.
 

Lying across the gap is a piece of ironwork which is thought to be an iron bed end which had been dumped on the ash mound after the site was abandoned.

 

This was the final and largest artifact recovered from the ash mound


This ended the investigation into the ash mound


 Fraser Miller
Archaeologist

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