“I do not doubt but that, by the help of a condensing engine, water might be much more highly impregnated with the virtues of the Pyrmont spring, and it would not be difficult to contrive a method of doing it.”
The manufacture of these waters was subsequently taken up by Priestley’s friend and satellite, as he called himself, Richard Bewley, of Great Massingham, an apothecary, and the inventor of the well-known “mephitic julep.” Bewley appears to have discovered that the addition of a small quantity of carbonate of soda to the water enabled it to absorb and retain an increased quantity of carbonic acid, and to him, therefore, is due the credit of first making what was long called “acidulous soda-water.” The receipt for its manufacture and use, given by Henry of Manchester, is sufficiently quaint to be worth reproduction:—
“To prepare Mr Bewley’s julep dissolve three drachms of fossil alkali in each quart of water, and throw in streams of fixed air till the alkaline taste be destroyed. This julep should not be prepared in too large quantities, and should be kept in bottles very closely corked and sealed. Four ounces of it may be taken at a time, drinking a draught of lemonade or water acidulated with vinegar or weak spirit of vitriol, by which means the fixed air will be extricated in the stomach.”
It is hardly to be supposed that the Royal Society Club in 1773 adopted all the social manners and customs of the period. Nevertheless, its members, who were among the most influential fellows of the Society, were evidently greatly impressed with the merits of Priestley’s soda-water, since the Council of the Society were moved to reward its discoverer with the Copley Medal.
In making the award on St Andrew’s Day 1773, Sir John Pringle, then President of the Royal Society, said:—
“For having learned from Dr Black that this fixed or mephitic air could in great abundance be procured from chalk by means of diluted spirits of vitriol; from Dr Macbride that this fluid was of a considerable antiseptic nature; from Dr Cavendish that it could in a large quantity be absorbed by water; and from Dr Brownrigg that it was this very air which gave the briskness and chief virtues to the Spa and Pyrmont waters; Dr Priestley, I say, so well instructed, conceived that common water impregnated with this fluid alone might be useful in medicine, particularly for sailors on long voyages, for curing or preventing the sea scurvy.”
To-day the Copley Medal is regarded as the highest award which it is in the power of the Society to bestow, and certainly no man starts his scientific career by acquiring it—not even for so signal an invention as that of soda-water.
Whilst Priestley was at Leeds a proposal was made to him that he should accompany Captain Cook in his second voyage to the South Seas. It probably arose from his connection with the Admiralty in the matter of his invention. He tells us that as the terms were very advantageous he consented to it, the heads of his congregation agreeing to keep an assistant to supply his place during his absence. But Mr Banks informed him that he was objected to by some clergymen in the Board of Longitude, who had the direction of this business, on account of his religious principles. “Whether,” said Huxley, in commenting on this circumstance in the course of his speech at the unveiling of the Priestley statue in Birmingham in 1874, “these worthy ecclesiastics feared that Priestley’s presence among the ship’s company might expose his Majesty’s sloop Resolution to the fate which aforetime befell a certain ship that went from Joppa to Tarshish, or whether they were alarmed lest a Socinian should undermine that piety which in the days of Commodore Trunnion so strikingly characterised sailors, does not appear.” The appointment was given to Reinhold Forster, a man, as Priestley fully admitted, far better qualified for the position.
CHAPTER VI
Becomes literary companion to Lord Shelburne—Goes abroad—His visit to Paris—His scientific work at Calne and in London—Continues his theological and metaphysical studies—His growing unpopularity—Leaves Lord Shelburne.