CALLED CASTLE HILL. 331 
mained entire, and retained its original form and 
colour; but, the wood was entirely absorbed; and 
the space, once occupied by the wood, was now 
filled with the fine aluminous red clay, of which the 
barrow was partially composed. It was thought 
by Dr. Black, of Manchester, that these branches 
of oak, were in a state of transition from vege- 
tables to fossils ; and, that, in some two thousand 
years more, this aluminous clay would have be- 
come stone, and the bark would have been car- 
bonized. In Fossil Wood, however, the fibres and 
grain of the wood are visible; but, in this alumin- 
ous clay, no trace of the wood was visible. 
PERPENDICULAR SHAFT—ANTICIPATED DEPOSIT. 
Most of the things found in the shaft, were si- 
milar to these discovered in the western drift. In 
sinking the shaft, however, from the top of the hill, 
it was observed by Mr. Mercer, that, on the north 
side, the earth was loose sand; but, that, on the 
south side, the earth was a compact body of clay 
and marl; and it was, therefore, thought by Mr. 
Mercer, that, the deposit contained in this barrow, 
would be found, under the coats of marl, on the 
south side of the shaft. Mr. Mercer also observed, 
that there was a short circular ridge on the south 
side of the top of the barrow. 
