Archaeology@Waterloo
The second series of geophysical surveys was carried out in January 2015 by GSB Prospection. The results of the larger surveys were excellent as a large number of archaeological features became evident, from buried structures and large pits containing burnt remains to evidence of the former garden layout of flower beds and paths. The magnetic survey also showed extensive evidence of fragments of iron buried beneath the surface, some of which were almost certainly pieces of buried or exploded ordnance which had been deposited during the battle.
Some of the recorded archaeological anomalies were immediiately investigated using augurs to test for depth and content.
Fluxgate Gradiometer (Magnetic) Survey of Hougoumont Farm
The Mag' survey is divided into four main areas
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1 The Approach Road Meadow (upper left)
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2 The western valley (lower left)
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3 the Walled Garden (upper right)
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4 The external eastern corner (middle right)
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NOTE: the blue areas indicate where a survey has been left unfinished within a given area, usually due to an obstruction within the survey grid.
In Area 1 it is possible to see the clear difference between the land within the bottom of the valley (the flood plain) and those areas above it as the lower lying land has much fewer small black and white 'blotches' on it. These are fragments of ferrous (iron) metal and as there are fewer in the valley bottom one can assume that those that once lay there have been covered up by silts forming in the valley. This means that the silts have been deposited since the iron was deposited. If any of these iron fragments date to the time of the Battle of Waterloo then they will now be protected under approximately half a metre of overburden.
The larger black area within this survey was tested by auger (see below) and found to be made up of half a metre deep of a dark grey/brown sandy silty material which contained fragments of coal and fired clay. This was capped with a thin layer of fired clay and coal fragments about 4cm in thickness and this in turn was covered in aproximately half a metre of clean natural soil overburden, the snady loam which covered the surrounding fields. The feature appears to represent a former pit or pond capped by rubble and then buried beneath soil washed into the valley bottom.
In Area 2 it is also possible to see the clear difference between the land within the bottom of the valley (the flood plain) as described in Area 1. The valley also has a linear black and white stripe across it. This is a result of the magnetometer recording the location of a linear magnetic object buried in the ground such as an iron water pipe or a series of ceramic drains. The black and white stripes can be seen as similar to a series of bar magnets on the end of each other. An area near to the great barn shows a large magnetic disturbance similar to that in area 1 where something has either been burnt or there is a collection of metal debris. Smaller magnetic areas are also evidence within the survey results. What these relate to is difficult to say without further archaeological investigation. One linear feature relates to the earthen ditch emerging from the brick culvert and another relates to the location of a former boundary.
In Area 3 one can see two black rectangular shapes next to two other uneven shaped features. These are remarkably similar to the feature in Area 1 that was tested with the augur, which suggests that it might have a simliar origin in time and function. If so one would expect to find a similar fill of fired clay and coal fragments.
In the extreme western corner of Area 3 in another area of intense magnetic disturbance similar to that highlighted in Area 1. It is possible that this is part of that same feature or is a similar one lying along side it. This general area around the Chateau or farm therefore has the appearance of some form of semi industrial activity taking place within it.
One of the most obvious feature in this area is the linear anomaly which runs in a North-South direction in the eastern-most end of the garden. This feature is either a boundary or more likely a path or track. What is surprising is that it does not appear to respect the walls of the garden but continues both to the south, where it appears once again in Area 4 and continues across the fields, but it also appears to cut the Hollow or Covered Way to its north (this feature is evident on earlier boundary maps). If this is a track or path then it must be earlier than both the garden walls and also the Hollow Way and therefore represents an early feature within the landscape. Another linear feature runs in an East-West direction, almost in the middle of the grided area, and this relates to the sharply sloping ground, lynchet or step within the walled garden. These lynchets are often formed when boundaries are placed on a slope and the land on either side is cultivated and then it moves and then levels out, thereby forming a step, rather than a smooth slope.
One of the strangest features in Area 3 is the row of four magnetic anomalies next to the blue rectangle in the eastern end of the grid These are denoted by a white area with a black spot in the centre. It would appear that these are pits full of magnetic material, similar to the larger black retangular pits discussed above. the orientation of this alignment suggests that it might relate to the Chateau phase of Hougoumont, rather than the later Farm period. What they represent is dificult to confirm without excavation. They might relate to four trees that were removed and their root bowls filled with brick debris, as with the other pits.
There are several other faint linear anomalies which appear to relate to the former garden layout, which could be paths or theedges of beds and plots.
In Area 4 there are two distinct lienear features. One is the one discussed which also appears in Area 3 and another appears to relate to a track that runs in an approximate Southwest-northeast direction, parallel to the nearby wall. The spacing of the edges, possibly ditches of this track suggest that it was relatively broad, possibly even representing some form of avenue within the trees of this former wooded area.
Resitivity (Earth Resistance) Survey of Hougoumont Farm
The Res' survey is divided into two main areas
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1 The Approach Road Meadow (upper left)
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2 The Walled Garden (upper right)
1 There is a circular feature in the corner of the Approach Road survey which appears to coincide with the remaims of one of the pits in the Mag survey.
2 There are a large number of features evident on the resistance surveys and most of these relate to the various paths and edges of the former gardens. Using these surveys in association with the other work undertaken it is possible to collect suficient data to understand parts of the former garden layout. The resistance data can also be fine tuned to look at different intensities within the generally blurred features. If one looks at the heavily disturbed areas, for example and filter this data it is possible to see what appear to be the remains of former structures within areas of rubble. As these do not show on the magnatic data one might assume that these structure were constructed of stone and not brick, suggesting they might be earlier that the present farm in date. There are also a series of circular pit-like features which appear to have disturbed the material around them.
Ground Penetrating RADAR (G.P.R.) Survey at Hougoumont Farm
The GPR survey was undertaken over the large area of concrete to the south of the southern gateway of Hougoumont Farm. The aim of the survey was to see if there was any obvious trace of the location where the human remains were alegedly buried or burnt. The results are produced as a series of area slices (one of which is shown below) through the ground at different depths. The survey represents 25 metres in length. Anomalies within the area are displayed in different shades or colours. Th results show a varied number of differential features which are initially difficult to interpret unless something very obvious is apparent. The plot shows some distinct features that lie below the surface of the ground.
During the survey a small sample of soil was analysed for evidence that a mass grave or burning pit was located in the area. The sample contained evidence that might prove to be conclusive in terms of indentifying areas of buried human rmeians in future prospection exercises. These results will need to be clarified and checked before further publication. Any interpretation of the GPR results will need to be eventually confirmed via excavation. the team is currently applying for permission to carry out further work on site.
The construction of an accurate map for the period of the battle, based upon real features either still visible or those discovered during archaeological survey, is now being undertaken. It will be an on-going process as more information is discovered and varified.