Ward, Joshua

SUBJECT AREA: Chemical technology

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b. 1685

d. 21 November 1761 London, England

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English doctor and industrial chemist.

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Ward is perhaps better described as a "quack" than a medical doctor. His remedies, one containing a dangerous quantity of antimony, were dubious to say the least. A fraudulent attempt to enter Parliament in 1717 forced him to leave the country quickly. After his pardon in 1733, he returned to London and established a successful practice. His medical prowess is immortalized in Hogarth's picture The Harlot's Progress.

Sulphuric acid had been an important chemical for centuries and Ward found that he needed large quantities of it to make his remedies. He set up works to manufacture it at Twickenham, near London, in 1736 and then at Richmond three years later. His process consisted of burning a mixture of saltpetre (nitre; potassium nitrate) and sulphur in the neck of a large glass globe containing a little water. Dilute sulphuric acid was thereby formed, which was concentrated by distillation. Although the method was not new, having been described in the seventeenth century by the German chemist Johann Glauber, Ward was granted a patent for his process in 1749. An important feature was the size of the globes, which had no less than fifty gallons' capacity, which must have entailed considerable skill on the part of the glassblowers. Through the adoption of Ward's process, the price of this essential commodity fell from £2 per pound to only 2 shillings. It provided the best method of manufacture until the advent of the lead-chamber process invented by John Roebuck.

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Further Reading

A.Clow and N.Clow, 1952, The Chemical Revolution: A Contribution to Social Technology, London: Batch worth.

C.Singer et al. (eds), 1958, A History of Technology, 7 vols, Oxford: Clarendon Press, Vol. IV.

LRD