Page:Dictionary of National Biography volume 09.djvu/343

 Galantes (edition of 1790), v. 156–62). Writing to the English secretary at war in March 1711, the Duke of Marlborough (Despatches, 1845, v. 269) begs his correspondent to tell Cavalier that unless he complies with the ‘just requests’ of Mme. Dunoyer ‘I shall be obliged to complain of him to the queen, that she may have justice done her out of his pension.’ Cavalier was now settled with a British pension in the United Kingdom. He spent much of the remainder of his life with the French colony founded at Portarlington by Ruvigny, earl of Galway [q. v.], and there he married the daughter of an aristocratic refugee, a Mademoiselle de Ponthieu. He is represented as having suffered frequently from pecuniary embarrassments, and these, it has also been said (, ii. 64), led to the issue of his ‘Memoirs,’ which were published by subscription at Dublin in 1726, with a dedication (signed ‘Jas. Cavallier’) to Carteret, then lord-lieutenant of Ireland. The volume professes to have been ‘written in French and translated into English,’ and is undoubtedly Cavalier's handiwork, though the ‘Biographie Universelle’ ascribes its composition to Galli, a French refugee. It is written with animation, and is full of military detail, but as a contribution to the history of the revolt in the Cevennes it is very fragmentary. Some of its most startling stories seem to be confirmed by the testimony of hostile witnesses, contemporaries of the events recorded (, i. 345 n. and 374 n.) The inaccuracies which have been detected in it are comparatively unimportant, with the exception of a grave misrepresentation of the spirit in which his companions opposed the treaty with Villars. Though the ‘Memoirs’ breathe a strongly protestant spirit, they are silent as to Cavalier's early gift of prophesying and preaching.

In 1727 Cavalier came to England with a recommendatory letter to the Duke of Newcastle from the Irish primate, Boulter. He was made a brigadier 27 Oct. 1735, and in March 1738 lieutenant-governor of Jersey, at several meetings of the estates of which island he presided. Appointed a major-general 2 July 1739, he died at Chelsea 17 May 1740, and was buried in Chelsea churchyard. Voltaire (Œuvres, xx. 397), who had known him, describes him as a ‘little fair man with a mild and agreeable countenance.’

Besides the authorities given below there may be consulted the article ‘Jean Cavallier and the Camisards’ in the ‘Edinburgh Review’ for July 1856. An idealised Cavalier figures in Ludwig Tieck's unfinished novel, ‘Der Aufrühr in den Cevennes’ (English translation, 1845), and he is the hero of Eugène Sue's historical romance, ‘Jean Cavalier ou les Fanatiques des Cévennes,’ translated into English as ‘The Protestant Leader, a novel,’ 1849.

 CAVALLO, TIBERIUS (1749–1809), natural philosopher, was born in Naples in 1749, his father being a physician practising in that city. At an early age he left Italy, and settled for life in this country. In October 1775 he published a notice of ‘Extraordinary Electricity of the Atmosphere observed at Islington.’ This was reprinted in ‘Sturgeon's Annals of Electricity’ (1843, p. 158). Cavallo was the inventor of several philosophical instruments and pieces of apparatus for electrical and chemical experiments. Much ingenuity was shown in their construction, all his instruments for the measurement of the quantity and force of electricity being remarkable for their extreme delicacy and correctness.

Cavallo was on 9 Dec. 1779 admitted as a fellow of the Royal Society. In 1781 he published a quarto volume entitled ‘A Treatise on the Nature and Properties of Air and other permanently Elastic Fluids.’ In this treatise he deals with chemistry and hydrostatics as they bear on the composition and physical properties of aeriform and other fluids. He examines with caution most of Dr. Priestley's experiments on air, and institutes many new ones, to determine more accurately the composition of the atmosphere and the conditions of inflammable and fixed air. Phlogisticated air forms the subject of inquiry, but it is evident that Cavallo could not receive the hypothesis of phlogiston, and yet did not feel himself on such sure ground as would justify his advancing any new doctrine. His investigations into the influences of air and light on the growth of plants are very original, and advanced him very nearly to the discovery of many new truths in connection with organic life.

In 1786 Cavallo published his ‘Complete Treatise on Electricity,’ which reached a third edition in 1795. It proves him to have been a true philosopher, holding his judgment suspended until he is satisfied by demonstrative evidence of the truth. In 1787 he published ‘A Treatise on Magnetism in Theory 