THE BONE CAVES OF THE PLYMOUTH DISTRICT. 95 
Prestwich, f.r.s., has kindly informed me that the collection in 
the Oxford Museum includes pieces of bone breccia, and a number 
of specimens (chiefly horse) labelled Plymouth, but without further 
specification. The Oreston examples are not displayed, but Mr. 
Prestwich doubts whether they would add to the published lists. 
The Oxford Museum possesses the valuable collection of Dr. Buck- 
land from Kirkdale, Kent's Hole, &c, and this is fully set out. 
Many specimens of this date found their way into private 
hands. Our own museum was utterly neglected. Mr. Pengelly 
describes* .this cavern as apparently in the same line as Mr. 
Whidbey's, " as if the various caverns had been so many enlarged 
portions of one and the same original line of fracture." j- The 
quarry face was 1090 feet from the quay or river margin, and 
about 487 feet from Mr. "Whidbey's last discovery. The face of 
the quarry was about sixty feet high, and the cavern, which 
was ninety feet long, ET.ET.E. to S.S.W., commenced about eight 
feet below the top of the cliff and extended to its base, where 
the bottom was not reached. At the top it was about two feet 
wide, gradually increasing downwards to a width of ten feet at 
the bottom. The uppermost eight feet were occupied with angular 
limestone debris, mixed with a small quantity of sand. The 
next thirty-two feet in depth contained "similar materials . . . 
(the sand being somewhat more abundant) with the addition of a 
considerable quantity of tough, dark, unctuous clay." Beneath 
this again was a bed of "dark, very tough, unctuous clay." The 
bones were found in connection with " a nearly vertical brecciated 
plate, or dyke, which the workmen denominated ' callis,' " stalac- 
titic in origin, containing masses of the fissure breccia, and having 
a general thickness of about two feet. "The bones were found 
alike in the 'callis,' and in the mass of heterogeneous materials 
beside it ; in the cemented and uncemented portions of the bed," 
"as frequently in the pure stalagmite as elsewhere." The roof of 
the fissure was formed of cemented limestone breccia, and Mr. 
Pengelly held that the cavern " originally communicated with the 
* " Geologist," 1859, pp. 434-444. Cited ''Devon. Asssoc. Trans.," vol. v. 
pp. 295-300. 
f Mr. Pengelly bases this view on the information as to position of an old 
quarryman; but it is not probable that the caverns of 1816 and 1820 were 
connected with that of 1858, if those of 1822-3 were, because Mr. Whidbey 
expressly states that the two earlier caverns were 180 yards to the east of 
the latter. (See ante.) 
