2 THE ESSEX NATURALIST
and rubbish has fallen down the shafts before they became
blocked, and the mounds of debris in Nos. 3 and 5 reach almost
to the bottom of the shaft. It is interesting to note that the holes,
which were blocked before 1887, have mounds of debris from
the floor to the base of the shaft and this presumably continues
up the shaft. These mounds of debris appear to be fairly
uniformly packed mounds of soil and almost free of rubbish. The
holes which have been blocked since 1887 apparently have debris
jammed part way down the shaft and other rubbish deposited on