Madame du Chàtelet has been much laughed at; but in the days when ladies take prizes in mathematics, that should be a thing of the past. Hard intellectual labor rather than the pursuit of pleasure characterised life at Cirey, or rather its inmates found their pleasure in their work. Madame would be translating Newton or studying Leibnitz. Her mathematical tutor worked at physical science in a gallery which had been built expressly for him. Voltaire would be aiding each in turn, or, ever faithful to his first love the drama, occupied with the writing or production of a tragedy or comedy for the theatre also attached to the premises. His production was as ever incessant. At the time of his first settlement there, Pope’s _Essay on Man_ had been published. It suggested a _Discourse on Man_, in which he sought not to justify the ways of God to man, but to make man contented with his lot, not vainly inquiring into the why and wherefore of things. With Madame he wrote _Elements of the Newtonian Philosophy_, a work highly praised by Lord Brougham, who says: “The power of explaining an abstract subject in easy and accurate language, language not in any way beneath the dignity of science, though quite suited to the comprehension of uninformed persons, is unquestionably shown in a manner which only makes it a matter of regret that the singularly gifted author did not carry his torch into all the recesses of natural philosophy.” The French Government, despite the influence of aristocratic friends, refused to print a work opposed to the system of Descartes, and the volume had to be printed in Holland. For Madame, who despised the “old almanack” histories then current, in place of which Voltaire aimed at producing something more profitable to the readers, he wrote his _Essay on the Manners and Spirit of Nations_, in which for the first time in modern literature he applied philosophy to the teaching of history. He dissipated the dull dreams and deceits of the monks, and fixed attention on the real condition of things. With Voltaire, the commonest invention which improves the human lot is of more importance than battles and sieges. He gives importance to the physical and intellectual improvement of man. Brougham remarks that Voltaire’s Philosophy of History was written as a prelude to the Essay on the Spirit of Nations, but the whole work deserves that title. Buckle classes him with Bolingbroke and Montesquieu, the fathers of modern history, and all sceptics; and even now, says Lecky, no historian can read him without profit. Other contributions to history were the _History of Charles XII._, a masterpiece of vivid and vigorous narrative, and _The Age of Louis XIV_. It was here he wrote his too famous _Pucelle_, which he afterwards described as “piggery,” as well as some of the most famous of his plays, including. _Ilzire, Zuline, L’Enfant Prodigue, Mahomet and Mérope_, the best of his tragedies. With