Interim report on Archaeological Training Excavation at Blackden in 2009 and 2010

Directors: Dr Mark Roberts, Professor Richard Morris

A survey made in 1789, the Tithe Map and first edition of the Ordnance Survey agree that a long building or line of structures lay aslant the south-western boundary of the site. By the end of the 19th century the building had disappeared and the boundary itself has been altered.

The maps disagree as to exactly where the building stood, and in 2009 the Trust undertook a short training excavation to locate and characterise its traces. We opened two test pits just inside the curtilage boundary, and one just outside in the adjoining field (named as ‘Barn Croft’ in the 1789 survey and later Tithe Award). The inner trial holes were at right angles to the long axis of the structure, whilst the trial trench in the field was set out at right angles to the anticipated gable end. This last trench located a broad band of clay that had been laid in a line corresponding to the gable end. Alongside the clay was charcoal from a burnt timber. A heading laid out at right angles from this trench duly intersected a similar band of clay in a position corresponding with the southern long wall of the building. Both deposits had escaped significant plough damage. At the time we thought it likely that the clay deposits were strip footings, but at that stage it was unclear what sort of structure they might have carried.

August 2010 saw a second season of excavation, again for training as well as research purposes, and now on a larger scale, aiming to expose the southern portion of the building. This we duly did, finding traces not of one building but several adjoining smaller structures erected at different times. At the northern end of the excavation the structure was footed on large unmortared sandstone blocks. To the south, a neighbouring foundation was formed of compacted brick rubble that had been rammed down in a trench. The putative clay ‘strip footings’ turned out to be remnants of a more extensive spread of clay found in association with a spread of comminuted and burnt brick – apparently, a kiln. Around the buildings, the sandy subsoil bears the marks of ploughing undertaken across the site since the building was levelled and associated activities ceased, following the ending of Toad Hall’s existence as a tenant farm in the 1870s.

A third season of work in 2011 will complete study of the structures, which on present evidence were mainly built of timber. Although the buildings were stripped of nearly all re-usable material around the time of their abandonment, a good deal can be told from fragments: small pieces of a closely-fitting stone flag floor, for instance, point to the storage of grain in one area, and similar evidence for roofing materials implies substantial timber trusses for the support of a heavy flag roof. Locally-made bricks are of at least six different kinds, implying either a number of episodes of construction, repeated patching, repeated re-use of the same building materials, or a combination of all three.

Blackden soil is rich in small glacial erratics. An innovation in 2010 was the keeping of all such pieces with a view to their petrological analysis, for the information this can provide on the sources of such stones and hence the directions and distances of their travels.

Geophysical Survey
 

October 2009

Dominic Powlesland and Ed Blinkhorn undertook two sample fluxgate gradiometer surveys on the land around Toad Hall. The sample surveys showed that gradiometry is an appropriate survey method on the soils around Toad Hall. More comprehensive surveys will be undertaken in the future to expose hidden evidence which will be correlated to give us an insight into the history of the site. When they have been analysed, the results will be published on the archaeology page.