To ascertain whether the contact of the saline solution with a metallic surface was necessary for the decomposition and transference, he introduced purified water into two glass tubes; a vessel containing solution of potassium chloride was connected with each of the tubes by means of asbestos; on introducing the wires into the tubes alkaline matter soon appeared in one tube, and acid matter in the other; and in the course of a few hours moderately strong solutions of potash and of hydrochloric acid were formed. Two tubes, one containing distilled water, the other a solution of potassium sulphate, were each connected by asbestos threads with a vessel containing a dilute solution of litmus; the saline matter was negatively electrified; and as it was natural to suppose that the sulphuric acid in passing through the water to the positive side would redden the litmus in its course, some slips of litmus paper were placed above and below the pieces of asbestos, directly in the circuit: it was found that the acid and alkali passed through the litmus solution without effecting any change in colour. “As acid and alkaline substances during the time of their electrical transfer passed through water containing vegetable colours without affecting them, or apparently combining with them, it immediately became an object of inquiry whether they would not likewise pass through chemical menstrua having stronger attractions for them; and it seemed reasonable to suppose that the same power which destroyed elective affinity in the vicinity of the metallic points would likewise destroy it, or suspend its operation, throughout the whole of the circuit.” To test this supposition, solution of potassium sulphate was placed in contact with the negative wire, and pure water in contact with the positive wire and a weak solution of ammonia was made the middle link of the conducting chain, so that no sulphuric acid could pass to the positive pole in the distilled water without passing through the solution of ammonia. In less than five minutes it was found that acid was collecting round the positive pole, and in half an hour the water was sour to the taste, and gave a precipitate with barium nitrate. Hydrochloric acid from common salt, and nitric acid from nitre were transmitted through concentrated alkaline menstrua under similar circumstances. Strontia and baryta readily passed, like the other alkaline substances, through hydrochloric and nitric acids; and _vice versâ_ these acids passed with facility through aqueous solution of baryta and strontia; but it was impossible to pass sulphuric acid through baryta or strontia, or to pass baryta and strontia through sulphuric acid, as precipitates of insoluble barium and strontium sulphate were formed. * * * * *