Extract

§ 1. The town of Droitwich is situated nearly in the centre of Worcestershire, about six miles from Worcester, on the road to Birmingham. For a very long time* the manufacture of salt has been carried on to a great extent in this place, and as I am not aware of the existence of any detailed account of the natural and chemical history of the brine springs from which it is procured, I take the liberty of laying before the Society some observations which I made on the spot in October, 1810, together with the results of some experiments I have since made, with the view of determining the chemical composition of the brine.†

§ 2. The brine-pits are in the centre of the town, situated in a narrow valley, in the bottom of which runs the small river Salwarp. The sides of the valley rise rather abruptly from the river. Doder Hill, on the right bank, which appeared to me to be the highest of the two sides, I measured with the barometer, and found it to be about eighty feet above the bed of the river.

§ 3. The prevailing rock around Droitwich is a fine-grained calcareo-argillaceous sandstone, of a brownish red colour, with occasional patches and spots which are greenish blue. At Doder Hill, where a vertical section of it is exposed, it contains beds of a greenish-grey colour, and of a more indurated texture, but which do not appear to differ materially in composition from the