it is evident that the source of these springs must be situated in much higher ground than that in which the pits are sunk.
§ 7. There are several pits on both sides of the river, but chiefly on the south side. The greater number of them, however, are not used, and the whole of the present extensive works are supplied from four pits. Indeed, the quantity of brine that is used bears but a small proportion to that which is allowed to run to waste; for, except when the reservoirs are filling, the brine is constantly flowing into the adjoining canal, through a channel cut for the purpose, near the mouth of the pits.
§ 8. The four pits that are worked at this time are distinguished by the names of Walker's Pit, Walwyn's Pit, Romney's Pit, and Stuckey's Pit. From each of these I obtained a bottle of the brine, for the purpose of submitting it to chemical examination. I also procured a bottle of the brine from Farley's Pit, on the north bank of the river, but which is not now worked.
I shall now lay before the Society the details of the process I adopted in this analysis.
§ 9. The brine from all the pits is perfectly limpid, and when held in a tumbler is colourless; a greater body of it, however, has a pale greenish hue, similar to that of sea-water. It has remained equally clear at the end of a year and a half in a bottle closely corked,
- Through the kindness of Thomas Farley, Esq. the principal proprietor of these works, I have learned, that the quantity of salt, annually made at Droitwich, is about 16,000 tons.—The principal part of this is consumed in England, and pays a duty of about £320,000.—The present market price of the salt is £31 per ton, £30 of which is duty.