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Rh great success in removing the objections which had been advanced by his antagonists against the comparatively recent formation of t-ho present continents. According to Cuvier, he ranked among the first geologists of his age. His principal geological work, Lettres physiques et morales rur rhistoire de la terre (6 vols. 8vo, The Hague, 1778), was dedicated to Queen Charlotte. It dealt with the appearance of mountains and the antiquity of the human race, explained the six clays of the Mosaic creation as so many epochs preceding the actual state of the globe, and attributes the deluge to the filling up o.f cavities supposed to have been left void in the interior of the earth. This attempt to reconcile religion and science, so often since repeated, was ingenious and for a time successful with most minds. The theory of the Mosaic days was maintained in one form or other by several later geologists of high repute, though it is scarcely now thought worth discussion by any to whom that title can justly be applied. Deluc s original experiments relating to meteorology are more valuable to the natural philosopher than most of his geological work; and he .discovered many facts of consider able importance relating to heat and moisture. He noticed the disappearance of heat in the thawing of ice about the same time that Black founded on it his ingenious hypothesis of latent heat. He ascertained that water was more dense about 40 Fahr. than at the temperature of freezing, expanding equally on each side of the maximum ; and he was the originator of the theory afterward re-advanced by Dalton, that the quantity of aqueous vapour contained in any space is independent of the presence or density of the air, or of any other elastic fluid ; though it appears difficult to reconcile this opinion with some of the experi ments of Deluc s great rival, Saussure, a philosopher who, as he very candidly allows, made in many respects more rapid progress in hygrometry than himself. Deluc s comparative experiments on his own hygrometer and on Saussure s show only that both are imperfect ; but it may be inferred from them that a mean between the two would in general approach much nearer to the natural scale than either taken separately. It appears also probable that Saussure s is rather less injured by time than Deluc s, which has been found to indicate an increasing amount of mean moisture every year. Deluc was a man of warm feelings, and of gentle and obliging manners, and his literary and scientific merits, as well as his unremitting attention to the service of the queen, insured her respect and kindness. He saw her daily for many years, and in his last illness, which was long and painful, she showed him repeated marks of benevolent regard. He died at Windsor on the 7th of November 1817. A brief notice of his more important works, in addition to that mentioned above, will give a clear idea of the nature and range of his scientific activity. His Recherches sur Us modifications de T Atmosphere (2 vols. 4to, Geneva, 1772 ; 4 vols. 8vo, Par. 1784), contains many accurate and ingenious experiments upon moisture, evaporation, and the indications of hygrometers and thermometers, applied to the barometer employed in determining heights. In the Phil. Trans., 1773, appeared his account of a new hygrometer, which resembled a mercurial thermometer, with an ivory bulb, which expanded by moisture, and caused the mercury to descend. The first correct rules ever published for measuring heights by the barometer were those he gave in the Phil. Trans., 1771, p. 158. His Lettres sur VHistoire physique de la Terre (8vo, Par. 1798) were addressed to Professor Blumenbach. The substance had already appeared in the Journal de Physique, for 1790, 1791, and 1798. The volume contains an essay written for a prize at Haarlem in 1791, but without success, on the existence of a General Principle of Morality. It also gives an interesting account of some conversations of the author with Voltaire and Rousseau, Deluc was an ardent admirer of Bacon, on whose writings he published two works, Bacon tel qu il est (8vo, Berlin, 1800), shewing the bad faith of the French translator, who had omitted many passages favourable to revealed religion, and Precis de la Philosophic de Bacon (2 vols. 8vo, Paris, 1802), giving an in. teresting view of the progress of natural science. Lettres sur It Christianisjne (Berlin and Hanover, 1801, 1803) was a contro versial correspondence with Dr Teller of Berlin in regard to the Mosaic cosmogony. His Traite elementaire de Geologic (8vo, Paris, 1809, also in English, by Delafite, the same year), was principally intended as a refutation of the Vulcanian system of Hutton and Playfair, who deduced the changes of the earth s structure from the operation of fire, and attributed a higher antiquity to the present state of the continents than is required in the Neptunian system adopted by Deluc after Dolomieu. He sent to the Royal Society, in 1809, a long paper on separating the chemical from the elec trical effect of the pile, with a description of the electric column and aerial electroscope, in which he advanced opinions so little in unison with the latest discoveries of the day, that the council deemed it inexpedient to admit them into the Transactions. He had, indeed, on other occasions shown somewhat too much scepticism in the rejection of new facts ; and he had never been convinced even of Cavendish s all-important discovery of the composition of water. The paper was afterwards published in Nicholson s Journal (xxvi.), and the dry column described in it was constructed by various experimental philosophers. Many other of his papers on subjects kindred to those already men tioned are to be found in the Transactions and in the Philo sophical Magazine. See Philosophical Magazine, November 1817.

 DELUGE, a submersion of the world, related by various nations as having taken place in a primitive age, and in which all, or nearly all, living beings are said to have perished. By this definition we exclude all partial floods, and also the theory which would account for deluge-stories as exaggerations of traditions of local inundations. Upon a low level of culture, as Von Hahn has shown, the memory of the most striking events is hardly preserved even for a few generations. It is best therefore to regard the story of the deluge as a subdivision of the primitive man s cosmogony. The problem with which he had to deal was a complicated one, given the eternity of matter to account for the origin of the world. The best solution which pre sented itself (and that only to the shrewder races) was to represent creation as having taken place repeatedly, and the world as having passed through a series of demolitions and reconstructions. (See COSMOGONY). This explains the confusion between the creation and the deluge noticed by various travellers, e.g., among the Iroquois and the Santals a confusion, however, which is only apparent, for the deluge is, when thoroughly realized, practically a second creation. Thus Manui the hero of the Indian flood-story, was, by permission of Brahma, the creator of the present human race. Noah is called by Arabic writers &quot; the second Adam,&quot; and Maui might with as good a right be called the Noah as the Adam of New Zealand. We, in the adult age of the world, have renounced those mythical forms of expression, but we still retain much of the feeling which prompted them. The wonder of creation is even to us constantly renewed in spring ; to primitive man it was renewed in a special sense in each of the great world-cycles of mythology. We may lay it down, then, as a canon at the outset, that the various deluge-stories must be viewed in combination, and explained on a common principle. At the same time we must be careful not to confound different &quot; deposits &quot; of tradition, and must regard primarily the earliest and most original forms of myths. As in the case of the cosmogonies, a few typical specimens will be all that can here be described. I. Among the Semitic races the seniority belongs to the Babylonians. Till lately, the only version of their story known to us was that of Berosus (Miiller, Fragmenta, ii. 501), who relates that the god Kronos appeared to Xisuthrus, tenth king of Babylon [cf. Noah, tenth patriarch] in a dream, and warned him of the coming deluge. The details remind us a good deal of the biblical narrative, ex cept that Xisuthrus is also accompanied by a steersman and by his near friends. Even the thrice repeated letting-out 