4 
mittee, for their kind assistance in making the arrangements 
for the meeting. 
The following communications were then made to the 
Societ}^ : — 
ON THE DISTURBANCES IN THE DISTRICT OF THE VALLEY 
OF THE DON. 
BY REV. WM. THORP, of Womerslkt. 
Upon the last visit of the Society to Sheffield, I had the 
pleasure of describing some of the geological features of the 
neighbouring district, and particularly those of the country 
between Rotherham and Sheffield. I have again taken the 
liberty of giving a brief mining notice of the disturbances of 
the same district, because they are not only of such enor- 
mous magnitude as to be of great interest to the geologist, 
but a knowledge of them is necessary to the successful min- 
ing operations of that neighbourhood. 
Upon the former occasion, it w^as contended by one party 
that not only w^ere the strata on the North side of the Don 
elevated above those of the South side, to the amount of 
600 yards in vertical height ; but that also there had been a 
horizontal lateral movement of the beds of the North side, 
in an eastward direction, to the length of five or six miles.* 
* The proofs then adduced in support of a lateral movement were — 1. That 
the various beds come from the North, up to the edge of the valley of the Don, 
but do not preserve their Northerly and Southerly direction across the valley, but 
are found several miles to the West ; e. £r.,the Silkstone coal ranges to Dropping 
Well, near Kimberworth, and is not found at the same depth until we arrive six 
miles West, at Sheffield town. 2. A sudden variation in the direction of the 
water levels, from North and South to East and West, down the valley of the 
Don. 3. A fault, of exactly fifty yards, in the ironstone at Tankersley Park, 
running North and South; and another fault in the same ironstone, in Tinsley 
Park, (ten miles distant,) running in the same direction, and being of the same 
amount, were supposed to be one and the same fault, before the lateral traction 
