RECENT DISCOVERY OF A DENE-IIOLE AT GRAYS. 155 
the Manager to the site of the new discovery, which is at the 
extreme northern end of the quarry. 
At this point the Thanet Sand, with its capping of Pleisto¬ 
cene river-gravel, has been worked back in earlier years, and 
forms a vertical cliff some hundred feet behind the present 
face of the underlying Chalk, and upon the wide ledge so formed 
a line of rails for the quarry railroad is laid down. 
Recently, it was desired to form a second line of rails close 
up to the cliff of Thanet Sand, and the latter was being slightly 
trimmed back to allow this to be done, when a cavity was broken 
into at the very base of the cliff, which proved, on further excava¬ 
tion, to be a dene-hole, similar to, but smaller than, those so 
well known at Hangman’s Wood, 1 1} mile to the east ; the pit 
was found to extend, in part, under the cliff and, in part, 
beneath the ledge formed by the removal of Thanet Sand in 
past years. 
This pit was an undoubted dene-hole, of the usual double 
trefoil in its plan (Fig. i), its longer axis running from north¬ 
west to south-east. 
The pit had been excavated by its constructors in such a 
way that the “ Bull Head ” Band of green-coated flints between 
the Chalk and Thanet Sand formed its actual ceiling, without 
any intervening chalk being left, as in the Hangman’s Wood 
dene-holes, to form a substantial roof. Probably on this ac¬ 
count, falls of flints and sand from the ceiling had taken place 
in two of the northern chambers (marked x x in the figure) ; 
and this fact, coupled with the presence of some threatening 
joints in the chalk of the end wall of the northern terminal 
chamber, had probably dissuaded the original constructors from 
proceeding further with their excavations, and this accounts 
for the unusually small size of this terminal recess. 
The floor of the dene-hole was approximately 44 feet below 
the original surface of the ground, and the shaft, some 2\ feet 
in diameter, was in the roof of the short, central connecting 
corridor between the two trefoil ends of the pit, but is now choked 
with a heterogeneous mass of fallen gravel from above. No 
grooves worn by ropes could be detected at the lower end of the 
plugged shaft, but three foot-holes were seen in the chalk walls 
below the shaft, two of these being in the eastern wall, one 
xSee “Essex Naturalist,” x, 1887, pp. 325-276. 
