C 549 ] 
yards deeper, and fome trees and fhrubs, that were 
round the edge of thefe pits, with the ground on 
which they grew, are funk down, near the bottom. 
I believe thefe pits at top may be about twelve yards 
diameter growing gradually narrower to a center, in 
fhape of a funnel or tun-difh. Under, it is fuppofed, 
is this cavity, through which the river now runs, ex- 
tending itfelf in one place under the river Avon- 
Looyd, at about a mile didance, where it broke out 
a few days after, in feveral places, on the oppofite 
fide thereof, where were three l'mall fprings. The 
reafon for this conjecture is, thefe fprings were ob- 
ferved to be always clear till a few days after the 
finking of this rock, but now continue to put forth 
large quantities of this water, which varies in colour 
agreeable to the water received in at the hole. I am, 
YQur Honours 
Abergavennny, Feb. 22, 
1756. mod humbe aid 
obedient fer/ant, 
Edward Matthews. 
Tab. XVII. 
a. The great chafm, which receives the greateft 
part of the water. 
b. Gravel walked away in the joint of the rock, 
through which runs into the cavity a confi- 
derable quantity of water, within four foot 
of the great hole. 
c. A precipice jud above the chafm. 
d. A hole funk in never before obferved. 
Vol. 4<>, 4 A e e. 
