496 REPORT—1883. 
of continuing his observations, and finds that percolating gauges are affected in the 
same way under the influence of barometric pressure as shown on a former occasion ; 
but in order to make a crucial test as to whether or not the water flowing from an 
artesian well would be affected by variations of barometric pressure, he instituted 
a series of observations at the end of the vear 1881 and the beginning of 1882, in 
connection with a well which he had had bored at the Croydon Rural Sanitary 
Authority’s works in the lower part of Mitcham parish. 
The well referred to has been bored through the London clay and Tertiary beds 
into the chalk, and a watertight bore-pipe inserted from top to bottom; having a 
steel shoe at the bottom it has been securely driven into the chalk, and the water 
overflows the surface. In making the experiments a length of iron pipe was fixed 
on the bore-pipe so as to bring it some feet above the ground level, and in the side 
of this pipe a small aperture was made in order to allow the overflowing water to 
escape, the result being that the water was headed up above the aperture about 
2 feet. A float fitted with graduated rod was floated on the water in the bore- 
Pipe, and from the observations made in this way it was found that whenever there 
was a fall in the barometer the column of water in the bore-pipe increased in 
altitude; while, on the other hand, for every rise in the barometer there was a 
corresponding fall in the column of water in the bore-pipe. 
The results of the observations are shown upon a diagram, and establish the fact, 
already very clearly demonstrated with reference to the gaugings of the bourne-flow 
at Croydon, that barometric pressure does exercise a considerable influence in 
accelerating or retarding the escape of water from the ground, the cause of which 
the author attributes, as on a former occasion, to the expansion and condensation 
of the air and gases held by the water, which at a period of low barometric 
pressure have a tendency to escape and so facilitate the flow of water, while under 
the conditions of high barometric pressure the tendency is in the opposite 
direction, and retards the flow of the water. 
SATURDAY, SEPIEMBER 22. 
The following Papers and Report were read :— 
1. Some additional notes on Anthracosaurus Edgei (Baily sp.), a large 
Sauro-Batrachian from the Lower Coal Measures, Jarrow Colliery, near 
Castlecomer, County Kilkenny. By Wiu1am Hexurer Baty, F.L.S., 
F.G.S., M.BR.LA. 
At the meeting of the British Association held at Dublin in 1878 a ‘ Notice of 
some additional Labyrinthodont Amphibia and Fish from Jarrow Colliery, County 
Kilkenny,’ was read by the author. In this communication he alluded to a large 
batrachian he had previously described, and named Anthracosaurus Edgei, in a 
paper read before the Royal Irish Academy, January 18, 1873. He then estimated 
from the remains of that fossil, as then known, that it indicated an animal of from 
eight to ten feet in length. 
Since that time, and during the present year, through the kindness of Joseph 
Dobbs, Esq., J.P., proprietor of the colliery, who has most liberally aided the author 
in these investigations, he has been enabled to obtain, in addition to most interest- 
ing fish-remains, for the collection of the Geological Survey of Ireland, a more 
complete example of this, perhaps the largest sauro-batrachian extant. 
The drawing illustrating this communication exhibited as exact a representation 
as could be taken of this remarkable fossil, of the natural size. It shows the 
impression of a somewhat triangularly shaped head, viewed from the inferior or 
palatal surface. It measures twelve inches in length and ten inches in breadth. 
The vertebral column, as preserved, numbers about sixty separate elements, 
