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were drawn up by ropes, probably of bide, or ascended by 
means of a ladder, which would be most probably made by 
cutting notches in a tree stem. The principal instrument used, 
both in sinking the shaft and working the galleries, was a pick 
made from the antler of the red deer, many examples of which 
were found. When a new pit was sunk, the material excavated 
went to fill up an old one. 
Ancient pits of the Grime’ s-Graves type must be carefully 
distinguished from certain modern shafts which exist in con- 
siderable numbers, and are for the purpose of obtaining chalk 
where it is some distance below the surface, and yet required for 
economical purposes. Mr. Aubrey Strahan of the Geological 
Survey, informs me that there are many such shafts in brick- 
yards in the country west of Windsor; and Mr. H. B. Wood- 
ward has lately called my attention to a paper by the late Dean 
Bucklandon the ‘Plastic Clay’* (the old name for the Wool- 
wich beds), in which mention is made of a shaft of this character 
at ‘ the base of the north-east extremity of Shooter’s Hill.’ 
Buckland states that ‘ in the same field with the clay-pits, and 
on the north side of them,, a shaft is sunk 120 feet to the sur- 
face of the subjacent Chalk, which has been extracted to the 
further depth of 24 feet, being the object for which the shaft 
was made. He also gives instances of the way in which the 
‘ Plastic Clay ’ upholds the water in the district, and throws out 
a line of springs at its outcrop. 
Pits of the kind known as Danes’ Holes, abound in the 
neighbourhood of Dartford, Cray ford, and Bexley, and near 
the village of East Tilbury, on the northern bank of the 
Thames. Similar excavations are said by the author of 
Murray’s Handbook to Kent to exist on either bank of the 
Somme as high as Peronne, in the diocese of Amiens. The 
tradition of Picardy asserts that ‘ these caverns were used for 
the retreat and concealment of the inhabitants in time of war, 
whence their ordinary name, les souterrains des guerres .’ Those 
in the neighbourhood of Crayford are thus described in Hasted’s 
History of Kent, vol. i. 1778 : ‘ There are now to be seen, as 
well on the heaths near Crayford as in the fields and woods 
hereabouts, many artificial caves or holes in the earth, some of 
which are 10, some 15, and others 20 fathoms deep. At the 
mouth, and thence downward,, they are narrow, like the tunnel 
of a chimney, or passage of .a well, but at the bottom they are 
large and of great compass, insomuch that some of them have 
several rooms or partitions one within another, strongly vaulted 
and supported with pillars of chalk.’ Hasted remarks that 
many of those on Dartford Heath ‘ have been stopped up of 
late,’ to prevent the frequent accidents from men and cattle 
* Trans. Geol. Soc. 1st series, vol. iv. p. 277. 
