Clavel (Adolphe), French Positivist and physician, b. Grenoble, 1815. He has written on the Principles of 1789, on those of the nineteenth century, on Positive Morality, and some educational works.

Clavel (F. T. B.), French author of a Picturesque History of Freemasonry, and also a Picturesque History of Religions, 1844, in which Christianity takes a subordinate place.

Clayton (Robert), successively Bishop of Killala, Cork, and Clogher, b. Dublin, 1695. By his benevolence attracted the friendship of Samuel Clarke, and adopted Arianism, which he maintained in several publications. In 1756 he proposed, in the Irish House of Lords, the omission of the Nicene and Athanasian Creeds from the Liturgy, and stated that he then felt more relieved in his mind than for twenty years before. A legal prosecution was instituted, but he died, it is said, from nervous agitation (26 Feb. 1758) before the matter was decided.

Cleave (John), bookseller, and one of the pioneers of a cheap political press. Started the London Satirist, and Cleave’s Penny Gazette of Variety, Oct. 14, 1837, to Jan. 20, ’44. He published many Chartist and Socialistic works, and an abridgment of Howitt’s History of Priestcraft. In May, ’40, he was sentenced to four months’ imprisonment for selling Haslam’s Letters to the Clergy.

Clemenceau (Georges Benjamin Eugene), French politician, b. Moulleron-en-Pareds, 28 Sept. 1841. Educated at Nantes and Paris, he took his doctor’s degree in ’65. His activity as Republican ensured him a taste of gaol. He visited the United States and acted as correspondent on the Temps. He returned at the time of the war and was elected deputy to the Assembly. In Jan. 1880 he founded La Justice, having as collaborateurs M. C. Pelletan, Prof. Acollas and Dr. C. Letourneau. As one of the chiefs of the Radical party he was largely instrumental in getting M. Carnot elected President.

Clemetshaw (C.), French writer, using the name Cilwa. B. 14 Sept. 1864 of English parents; has contributed to many journals, was delegate to the International Congress, London, of ’87, and is editor of Le Danton.

Clemens (Samuel Langhorne), American humorist, better known as “Mark Twain,” b. Florida, Missouri, 30 Nov. 1835. In ’55 he served as Mississippi pilot, and takes his pen name from the phrase used in sounding. In Innocents Abroad, or the New Pilgrim’s Progress, ’69, by which he made his name, there is much jesting with “sacred” subjects. Mr. Clemens is an Agnostic.

Clifford (Martin), English Rationalist. Was Master of the Charterhouse, 1671, and published anonymously a treatise of Human Reason, London, ’74, which was reprinted in the following year with the author’s name. A short while after its publication Laney, Bishop of Ely, was dining in Charterhouse and remarked, not knowing the author, “’twas no matter if all the copies were burnt and the author with them, because it made every man’s private fancy judge of religion.” Clifford died 10 Dec. 1677. In the Nouvelle Biographie Générale Clifford is amusingly described as an “English theologian of the order des Chartreux,” who, it is added, was “prior of his order.”

Clifford (William Kingdon), mathematician, philosopher, and moralist, of rare originality and boldness, b. Exeter 4 May, 1845. At the age of fifteen he was sent to King’s College, London, where he showed an early genius for mathematics, publishing the Analogues of Pascal’s Theorem at the age of eighteen. Entered Trinity College, Cambridge, in ’63. In ’67 he was second wrangler. Elected fellow of his college, he remained at Cambridge till 1870, when he accompanied the eclipse expedition to the Mediterranean. The next year he was appointed Professor of mathematics at London University, a post he held till his death. He was chosen F.R.S. ’74. Married Miss Lucy Lane in April, ’75. In the following year symptoms of consumption appeared, and he visited Algeria and Spain. He resumed work, but in ’79 took a voyage to Madeira, where he died 3 March. Not long before his death appeared the first volume of his great mathematical work, Elements of Dynamic. Since his death have been published The Common Sense of the Exact Sciences, and Lectures and Essays, in two volumes, edited by Leslie Stephen and Mr. F. Pollock. These volumes include his most striking Freethought lectures and contributions to the Fortnightly and other reviews. He intended to form them into a volume on The Creed of Science. Clifford was an outspoken Atheist, and he wrote of Christianity as a religion which wrecked one civilisation and very nearly wrecked another.

Cloots or Clootz (Johann Baptist, afterwards Anacharsis) Baron du Val de Grâce, Prussian enthusiast, b. near Cleves, 24 June, 1755, was a nephew of Cornelius de Pauw. In 1780 he published the The Certainty of the Proofs of Mohammedanism, under the pseudonym of Ali-gier-ber, an anagram of Bergier, whose Certainty of the Proofs of Christianity he parodies. He travelled widely, but became a resident of Paris and a warm partisan of the Revolution, to which he devoted his large fortune. He wrote a reply to Burke, and continually wrote and spoke in favor of a Universal Republic. On 19 June, 1790, he, at the head of men of all countries, asked a place at the feast of Federation, and henceforward was styled “orator of the human race.” He was, with Paine, Priestley, Washington and Klopstock, made a French citizen, and in 1792 was elected to the Convention by two departments. He debaptised himself, taking the name Anacharsis, was a prime mover in the Anti-Catholic party, and induced Bishop Gobel to resign. He declared there was no other God but Nature. Incurring the enmity of Robespierre, he and Paine were arrested as foreigners. After two and a half months’ imprisonment at St. Lazare, he was brought to the scaffold with the Hébertistes, 24 March, 1794. He died calmly, uttering materialist sentiments to the last.