invariably adopted in ridding themselves of an obtrusive competitor. CHAPTER V FORMATION AND EXTENT OF THE CHESHIRE DEPOSITS The theories propounded and the conclusions arrived at on the subject of the formation of the Cheshire salt beds do not differ in any important particular from those which have been put forward, investigated, and accepted with regard to rock-salt deposits in all parts of the world, but, because of the enormous geologic and climatic changes that have occurred in the English county since a salt basin was in course of formation there, scientists were slower in accepting those conclusions in respect of our home deposits than in the case of the salt areas which are found in the Runn of Kutch, at Lake Elton, or Black Gulph on the eastern side of the Caspian Sea. The facts that the chief accompaniment of every known deposit of rock-salt is clay, and that clay is deposited in water, formed the basis of the erroneous theory that because salt is a deposit out of water, and sea-water contains salt, all salt beds must have been deposited in the sea. But salt does not mix mechanically with water and has not been deposited like sedimentary rocks; it forms a solution, and not until the solution becomes super-saturated does it crystallize out. Now sea-water rarely contains more than 3½ per cent. of salt, and since the solution must contain at least 26 per cent. of salt before the salt will crystallize out, and, provided it is left from contact with the air, a solution of this strength may be left for an indefinite length of time without a single particle of salt depositing, the old theory that all salt beds were deposited in the sea had to be abandoned. The theory of the sea-water deposition of salt beds having been disposed of, it was long a popular idea that the beds of rock-salt owed their formation to volcanic action. Professor C. Thompson was of opinion that some enormous electrical force had been at work in its crystallization; Professor Silvestri found quantities of chloride of sodium varying from 50 to 90 per cent. in different sublimations in the lava which was erupted from Etna in 1863; Bunsen discovered a considerable but less important sublimation of chloride of sodium in the lava erupted from Hekla in 1854; and G. F. Rodwell and H. M. Elder also recognized small traces of sodic chloride as one of the products of volcanic action. In a paper contributed to the Manchester Geological Society, in 1842, on “An Inquiry into the Origin of the Salt Field of Cheshire,” so respected an authority as Ormerod stated his conclusions as follows-- “(_a_) That from the lithological character of the accompanying beds and partings, and from the regularity in the thickness of the respective beds, as far as the same were now known, these salt beds were, in his opinion, deposited from an aqueous menstruum, and had not been injected.