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the gault were wanting, or thinned out, and the bottom of the 
wells rested on beds; in all probability of Paleozoic or primary 
rocks. Thus to the North of the Thames in the Eastern Counties, 
Mr. Godwin Austen’s surmises were proved to be correct. South 
of the Thames, Mr. Dowker drew attention to the great Sub- 
Wealden boring in 1872, about which some £6,000 was spent, and 
a depth of 1,841 feet reached without getting to the bottom of the 
Oxford clay, when the undertaking was abandoned; proving, 
however, that the secondary rocks were here met with in unusual 
thickness. 
Mr. Dowker recorded his observations on the Boulonnais area, 
which he visited with several members of the Geologists’ Associa- 
_ tion, and under the guidance of the most distinguished Geologists 
of Northern France, in 1878, and explained the position of the 
coal there met with. 
Lastly, he gave particulars of the deep borings in Kent that 
have recently been made, viz., at Chatham Dock-yard, to a depth 
of 965 feet, and all the secondary beds betoken the lower green- 
sand down to the Oxford clay were wanting, the latter being 
pierced to a depth of 20 feet. 
Also the deep boring at the Convict Prison, East Cliff, Dover, 
which penetrated to a depth of 931 feet. Below the gault,.63 feet 
in lower greensand, and the remaining 50 feet in Wealden beds. 
He stated that we may conclude, with certainty, that the 
primary rocks underlie the Northern parts of Kent at a less depth 
than 2,000 feet, and therefore coal measures will probably be met 
with. But the sections given seem to show that the overlying 
beds are thinnest towards the North East, and he concludes that the 
Isle of Thanet would probably be a more favourable site for the 
proposed boring. 
The chance of finding carboniferous limestone was, however, 
not finding coal. And the coal measures rested on beds so distorted 
that they were probably in ridges beneath the London Basin, and it 
was impossible to predict where the boring would strike the under- 
ground strata. The probability that the coal measures had thinned 
out or been denuded was also touched upon. The conclusion being 
that such was not the case to any considerable extent in the area. 
Mr. Dowker’s remarks were illustrated by numerous maps and 
sections, which were some of them furnished by Mr. Toply, of 
the Geological Survey ; and, in preparing the paper, all available 
sources of information on the subject, derived from the voluminous 
