Page:Quarterly Journal of the Geological Society of London, vol. 33.djvu/27

Rh bring that about), there would not be much difference between the Ham-Hill section and several other sections near Sherborne.

Ham Hill has always been a puzzle to the geologist; but if we place it on the same horizon as the so-called "Lias Sands" at Bradford, the difficulty is at once cleared up.

Mr. Moore, in his paper "On the Middle and Upper Lias of the South-west of England," speaking of Ham Hill says:—

"The workable freestone at this spot is 58 feet thick, and almost entirely composed of comminuted shells, united by an irony cement, and is a remarkable deposit; for though attaining so considerable a thickness, it does not appear to be represented in any other locality. It has been largely worked for centuries, and yields a very excellent stone, of a light-brown colour, due to the presence of carbonate of iron, an analysis of the deposit proving it to contain 14 per cent of metallic iron".

The best Gloucestershire equivalent of this bed is to be seen in the straight wall of rock at Crickley Hill, which latter section we consider the equivalent of the freestone-beds at Ham Hill, and the