dependence, consent to make America dependent upon France. The indifferent reception which he met with in society was probably owing to this party violence full as much as to the dislike of his Unitarian opinions. But it must be added, that his temper was so mild, and his manners so gentle, as to disarm his most prejudiced adversaries whensoever they came into his society. Many instances of this are given in his correspondence, of which one may be cited. He happened to visit a friend whose wife received him in her husband's absence, but feared to name him before a Calvinistic divine present. By accident his name was mentioned, and the lady then introduced him. But he of the Genevan school drew back, saying, "Dr. Joseph Priestley?" and then added in the American tongue, "I cannot be cordial." Whereupon the Doctor, with his usual placid demeanour, said that he and the lady might be allowed to converse until their host should return. By degrees the conversation became general; the repudiator was won over by curiosity first, then by gratification; he remained till a late hour hanging upon Priestley's lips; he took his departure at length, and told the host as he quitted the house, that never had he passed so delightful an evening, though he admitted that he had begun it "by behaving like a fool and a brute." One such anecdote (and there are many current) is of more force to describe its subject than a hundred laboured panegyrics.

After the loss of his wife and his younger and favourite son, he continued with unabated zeal to pursue his theological studies, and published several works, both controversial and historical, beside leaving some which have been given to the world since his decease. He endeavoured, too, as far as he could, to propagate the tenets of Unitarianism, and to collect and extend a congregation at Philadelphia attached to that doctrine. At one time, in the summer of 1797, entertaining hopes of peace in Europe, he had resolved to

visit France, where he might communicate personally with his English friends; and he even thought of making a purchase in that country on which he might reside during a part of each year. So nearly did he contemplate this removal, that we find him desiring the answers to letters he was writing might be sent to the care of Messrs. Perregaux at Paris. The revolution of Fructidor, however (4th September, 1797), put an end to all prospects of peace, and the war soon raged in every quarter with redoubled fury. He seems now to have derived his chief comfort from tracing the fancied resemblance between the events passing before him and the prophecies in Scripture; though occasionally he felt much puzzled, and the book of Daniel, especially, appears to have given him trouble and perplexity. When the peace came at last, his health was too much broken to permit any plans to be executed such as he had four years before contemplated.

In 1802 he became a confirmed invalid, suffering from internal, and apparently organic, derangement. His illness was long and lingering, and he suffered great pain with perfect patience for two years. The prospect of death which he had before him did not relax his application to literary labour, his faculties remaining entire to the last. Neither did that awful certainty, ever present to his mind, affect him with sorrow or dismay. The same unshaken belief in a future state, the same confident hope of immortal life which had supported him under his affliction for the death of others, cheered him while contemplating the approach of his own. In this happy frame of mind he gently expired on the 6th of February, 1804, in the seventy-second year of his age.

His character is a matter of no doubt, and it is of a high order. That he was a most able, most industrious, most successful student of nature, is clear; and that his name will for ever be held in grateful remembrance by all who cultivate physical science, and

placed among those of its most eminent masters, is unquestionable. That he was a perfectly conscientious man in all the opinions which he embraced, and sincere in all he published respecting other subjects, appears equally beyond dispute. He was, also, upright and honourable in all his dealings, and justly beloved by his family and friends as a man spotless in all the relations of life. That he was governed in his public conduct by a temper too hot and irritable to be consistent either with his own dignity, or with an amiable deportment, may be freely admitted; and his want of self-command, and want of judgment in the practical affairs of life, was manifest above all in his controversial history; for he can be charged with no want of prudence in the management of his private concerns. His violence and irritability, too, seems equally to have been confined to his public life, for in private all have allowed him the praise of a mild and attractive demeanour, and we have just seen its great power in disarming the prejudices of his adversaries.

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CAVENDISH.

A GREATER contrast between two men of science, both eminent benefactors to the same branch of knowledge, can hardly be imagined than Cavendish offers to Priestley. He was thoroughly educated in all branches of the Mathematics and Natural Philosophy; he studied each systematically; he lived retired from the world among his books and his instruments, never meddling with the affairs of active life; he passed his whole time in storing his mind with the knowlege imparted by former inquirers and in extending its bounds. Cultivating science for its own sake, he was slow to appear before the world as an author; had reached the middle age of life before he gave any work to the press; and though he reached the term of fourscore, never published a hundred pages. His methods of investigation were nearly as opposite as this diversity might lead us to expect; and in all the accidental circumstances of rank and wealth the same contrast is to be remarked. He was a duke's grandson; he possessed a princely fortune; his whole expenditure was on philosophical pursuits; his whole existence was in his laboratory or his library. If such a life presents little variety and few incidents to the vulgar observer, it is a matter of most interesting contemplation to all who set its just value upon the cultivation of science, who reckon its successful pursuit as the greatest privilege, the brightest glory of our nature.

Henry Cavendish was born at Nice, whither his mother's health had carried her, the 10th of October, 1731. He was the son of Lord Charles Cavendish, the

late Duke of Devonshire's great uncle, by the daughter of Henry Grey, Duke of Kent. His family, aware of the talents which he early showed, were anxious that he should take the part in public life which men of his rank are wont to do, and were much displeased with his steady refusal to quit the studies which he loved. An uncle, disapproving of the course pursued towards him made him his heir; and so ample a fortune came into his possession that he left at his death a million and a quarter of money.* The Mathematics, and the various branches of Natural Philosophy, were the chief subjects of his study, and of all these sciences he was a consummate master.

The discoveries of Black on carbonic acid and latent heat, appear to have drawn his attention to the cultivation of pneumatic chemistry; and in 1766 he communicated to the Royal Society his experiments for ascertaining the properties of carbonic acid and hydrogen gas. He carried his mathematical habits into the laboratory; and not satisfied with showing the other qualities which make it clear that these two aëriform substances are each sui generis, and the same from whatever substances, by whatever processes, they are obtained; nor satisfied with the mere fact that one of them is heavier, and the other much lighter, than atmospheric air,-he inquired into the precise numerical relation of their specific gravities with one another and with common air, and first showed an example of weighing permanently elastic fluids: unless, indeed, Torricelli may be said before him to have shown the relative weight of a column of air and a column of mercury or the common pump to have long ago

M. Biot's article in the Biog. Univ. makes him the son of the Duke of Devonshire, and states his yearly income at £300,000 sterling, and yet gives the property he left at only £1,200,000-so that he must have spent £300,000 a-year, and also dissipated five millions. Such errors seem incredible.

†Three papers containing experiments on factitious air. Phil. Trans. 1766, p. 141.