BRlTISIt ASSOCIATION MEETINO. 
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roof, cii^lii foot ill tliicknoss, was of sound uiibrokcMi limestone, and that, the 
stones and otiicr materials could not li;ivc fallen in from above ; but then, unfor- 
tunately, they, with ccpial posit ivity, alhi-m that tiierc was no external opening 
whatever — vertieal, teriniual, or lateral; and, in their endeavours to account for 
the ))rcscuee of tlu; bones and rock-debris in what they believe to have been 
merely a blind cavity iu tiie rock, they incline to iiic opinion that the rock lias 
grown round the aceumulation which it contains — ^^just as some persons ask us 
to believe tluit rocks have grown aro\ind live toads and frogs. 
It will be remembered that iu Mr. Wliidbey's description of the two first 
caves he most decidedly gives it as his opinion that there never were any indi- 
cations of a communication with the surface ; indeed, iu his first letter " Ik; 
saw no possibility of the cavern having had any external communication 
through tlie rock iu which it was inclosed;" and although in his letter to Mr. 
Barrow, descriptive of the third cave, he admits that " there were joints not so 
close but that water might have dripped into the- cavern," he adds " I have 
not seen anything to encourage the idea that the cavern had a coniinunicatiou 
with the surface since the flood." 
In liis " ReliquiiB Diluviana!," Dr. Biickland, who had visited Oreston, says, 
" In speaking of the bones at Oreston in my former ])apcr on Kirkdale, I had 
expressed a decided opinion that the caverns in which they occur must have 
had sonic communication with the surface, through which the bones may have 
been introduced ; and Mr. Whidbey has since found reason to adopt the same 
opinion."* 
The late Sir Henry de la Beclie, in his " Report on the Geology of Corn- 
wall, Devon, and West Somerset," says "In one of our visits to the Oreston 
quarries we obtained two teeth of a rhinoceros at the bottom of a narrow 
fissure, amid a dark clay, apparently impregnated with animal-matter, iu an old 
unnoticed part of an excavation. Considerable angular masses and smaller 
fragments of limestone often occur in the ossiferous and other fissures, and it 
can be readily understood that before these cracks became filled by fragments 
detached from the sides, and by the loam and sand, multitudes of animals 
ranging the ground above could have fallen into them, more particularly when 
chased by beasts of prey, often themselves the victims of their own eagerness 
and voracity either dui-iiig the chase, or when the dead animals were visible 
in the fissures. "f 
As the workmen entered the cavern at the top, in the ordinary course of 
working vertically downwards the greater part of the roof was destroyed before 
I visited Oreston ; nevertheless a portion, and, I think, a sufficient portion for 
the purpose, remained. It was evidently a mass of limestone-breccia, made up 
of large angular fragments cemented by carbonate of lime, and easily enough 
ndstakcn, without a careful inspection, for ordinary lunestone somewhat rich 
in coarse veins. I called the attention of the workmen to it, and explained my 
opinion respectmg its origin ; to this they offered no objection further than 
that it was solid, and required blasting quite as much as the limestone else- 
where. This appears to have been Mr. WHiidbey's test ; for, in his first letter 
to Sir Joseph Banks ; he says, "In the contract of quarrying there are two 
prices, one for rock, another for clay, earth, and rubbish ; and two ofiicers at- 
tend, one for the Crowi, and the other on the part of the contractors, who 
measure the contents of all caverns that contain clay, or other soft materials ; 
it is only necessary to mention that these officers state that the rock surround- 
ing the cavern was equally hard with the other parts, requiring the same force 
to blast, and that the quarrying was paid for accordingly. "J 
* Reliquce Diluvianae, page 80. 
t Do la Beche's " Report on Cornwall," &c., p. U3. 
t Philosophical Transactions, 1817, p. 177. 
