Page:Encyclopædia Britannica, Ninth Edition, v. 6.djvu/868

832 colour, and quality, under cultivation, as does the apple in temperate regions, while the recognized and named varieties of the one fruit are quite as numerous as those of the other. Regarding this fruit Mr W. G. Palgrave (Central and Eastern Arabia) remarks &quot;Those who, like most Europeans at home, only know the date from the dried specimens of that fruit shown beneath a label in shop- windows, can hardly imagine how delicious it is when eaten fresh and in Central Arabia. Nor is it, when newly gathered, heating, a defect inherent to the preserved fruit everywhere ; nor does its richness, however great, bring satiety ; in short it is an article cf food alike pleasant and healthy.&quot; In the oases of Sahara, and in other parts of Northern Africa, dates are pounded and pressed into a cake for food ; and it is said that there, the fruit is the food of man and beast, and is eaten by horses and camels, and even by dogs. The dried fruit used for dessert in European countries contains more than half its weight of sugar, about 6 per cent, of albumen, and 12 per cent, of gummy matter. All parts of the date palm yield valuable economic products. Its trunk furnishes timber for house-building and furniture ; the leaves supply thatch ; their footstalks are used as fuel, and also yield a fibre from which cordage is spun.

Date sugar is a valuable commercial product of the East Indies, obtained from the sap or toddy of Elate sylvestris, a tree so closely allied to the date palm that it has been supposed to be the parent stock of all the cultivated varieties. The juice, when not boiled down to form sugar, is either drunk fresh, or fermented and distilled to form arrack. The uses of the other parts and products of this tree are the same as those of the date palm products. Date palm meal is obtained from a small species, Elate farinif era, growing in the hill country of southern India ; it is occa sionally resorted to in times of distress or famine.  DAUBENTON, (1716-1800), a distinguished naturalist, was born at Montbar, in the department of the Cote d Or, in France, May 29, 1716. His father, Jean Daubenton, a notary, who destined him for the church, after putting him through a course of instruction under the Dominicans of Dijon, sent him to Paris to learn theology. The secret study of medicine, however, and the lectures of Baron, Mar- tinenq, and Col de Villars, of Winslow, Hunault, and Antoine de Jussieu, were more attractive to young Daubenton. The death of his father in 1736 set him free to follow his own inclinations, and he accordingly in 174X took the degree of doctor at Rheims, and returned to his native town with the intention of following the practice of medicine. But fortune destined him for a more brilliant career. It was about this time that Buffon, also a native of Montbar, had formed the plan of bringing out a grand treatise on natural history, and in 1742 he invited Daubenton to assist him by providing the anatomical descriptions for that work. The characters of the two philosophers were opposed in almost every respect. Buffon was violent and impatient ; Daubenton, gentle and patient ; Buffon was rash in his judgments, and imaginative, seeking rather to divine than to discover truths ; Daubenton was captious, and believed nothing he had not himself been able to see or ascertain. From nature each appeared to have received the qualities requisite to temper those of the other ; and a more suitable coadjutor than Daubenton it would have been difficult for Buffon to obtain. In the first section of the natural history Daubenton gave descrip tions and details of the dissection of 182 species of quad rupeds, thus procuring for himself a high reputation, and exciting the envy of Reaumur, who considered himself as at the head of the learned in natural history in France. A feeling of jealousy induced Buffon to dispense with the services of Daubenton in the preparation of the subsequent parts of his work, which, as a consequence, lost much in precision and scientific value. Buffon afterwards perceived and acknowledged his error, and renewed his intimacy with his former associate. The number of dissertations on natural history which Daubenton published in the memoirs of the French Academy is very great. Zoological descrip tions and dissections, the comparative anatomy of recent and fossil animals, vegetable physiology, mineralogy, experiments in agriculture, and the introduction of the merino sheep into France gave active occupation to his energies ; and the cabinet of natural history in Paris, of which in 1744 he was appointed keeper and demonstrator, was arranged and considerably enriched by him. From 1775 Daubenton lectured on natural history in the College of Medicine, and in 1783 on rural economy. He was appointed professor of mineralogy by the Convention at the Jardin du Roi ; and he gave lectures at the Normal School during the ephemeral existence of that institution. He was likewise one of the editors of the Journal des tfavans, and contributed to two encyclopaedias. As a lecturer he was in high repute, and to the last retained his popularity. In the winter of 1799 he was appointed a member of the Conservative Senate, but at the first meeting which he attended he fell from his seat in an apoplectic fit After a short illness he died at Paris, January 1, 1800.  DAUBENY, (1795-1867), an English chemist, botanist, and geologist, was the third son of the Rev. James Daubeny, and was born at Stratton, in Gloucestershire, February 11, 1795, and died December 12, 1867. In 1808 he entered Winchester School, and in 1810 he was elected to a demyship at Magdalen College, Oxford. The lectures of Dr Kidd at that university first awakened in him a desire for the culti vation of natural science. In 1814 he graduated with second class honours, and in the next year he obtained the prize for the Latin essay. From 1815 to 1818 he studied medicine in London and Edinburgh ; and in the latter city he attended the lectures of Professor Jameson on natural science. At that time the rival theories of the Huttonians and Wernerians were occupying the attention of geologists. In 1819 Daubeny, in the course of a tour through France, made the volcanic district of Auvergne a special study. By subsequent journeys in Hungary, Transylvania, Italy, Sicily, France, and Germany he extended his knowledge of volcanic phenomena ; and in 1826 the results of his observations were given in a work entitled A Description of Active and Extinct Volcanoes, a second edition of which was printed in 1848. An earlier treatise was An Essay on the Geology and Chemical Phenomena of Volcanoes, published at Oxford in 1824. Daubeny, in common with Gay-Lussac and Davy, held subterraneous thermic disturbances to be probably due to the contact of water with metals of the alkalies and alkaline earths. In November 1822 Daubeny succeeded Dr Kidd as professor of chemistry at Oxford, and twelve years later he was appointed to the chair of botany there. At the Oxford Botanic Garden he conducted numeraus experiments upon the effect of changes in soil, light, and the composition of the atmosphere upon vegeta tion. In 1830 he published in the Philosophical Transac tions a paper on the iodine and bromine of mineral waters. In the following year appeared his Introduction to the Atomic Theory, which was succeeded by a supplement in 1840, and in 1850 by a second edition. In 1831 Daubeny represented the universities of England at the first meeting of the British Association, which at his request held their next session at Oxford. In 1836 he communicated to the Association a report on the subject of mineral and thermal waters. In 1837 he visited the United States, and acquired there the materials for papers on the thermal springs and 