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to Civil History, to the History of Culture, to Natural History, Natural Philosophy, and Agriculture; from the Transactions of the Academy of Sciences at Brussels. 1 vol. 8vo. Leipsic, 1783.

It is observed by Mad. de Stael, that the English are much better acquainted than the French with the literature of Germany; but we have met with very few possessed of any knowledge of the works of this learned and celebrated writer; and, with the exception of one or two of his smaller essays, none of them, we believe, has ever been translated into the language of this country. In the above list, there are more than one work which might probably be published with advantage in the English tongue.(.) ADEN, a city on the Arabian coast, to the east of the straits of Babelmandel, the position of which only is mentioned, and that not very accurately, in the body of the work. It is situated in latitude 12° 50′ north, and longitude 45° 10′ east. According to the Arabians, it derives its name from Aden, the son of Saba and grandson of Abraham. Be this as it may, it was once the most flourishing city of Arabia, though it now presents little more than a heap of ruins surrounded with miserable huts. But it is nevertheless a place of considerable consequence on that coast, from the superiority of its harbour, and its other advantages for trade. It is accessible at all times of the year; and from it a constant intercourse may be maintained with the coast of Africa. Coffee of the best quality, and all the other articles which enter into the commerce of the Red-Sea may be procured at this port. In particular, it is the chief mart for the guns brought over from the north eastern districts of Africa; on which account this drug may be procured here at a cheaper rate than at Mocha. The English traders are much in favour at Aden.—See Salt’s Voyage to Abyssinia, and Milburn’s Oriental Commerce. ADHESION, a term chiefly used to denote the force with which the surface of a solid remains attached to the surface of a liquid, after they have been brought into contact. Suppose a polished glass plate to be suspended horizontally from one extremity of a balance, and to be exactly counterpoised by weights put into the opposite scale, if we bring this plate in contact with the surface of a quantity of mercury, we shall find that a certain additional weight must be placed in the opposite scale, in order to separate the glass from the mercury. The force which kept the two bodies in contact is called adhesion. Three sets of experiments on this subject have been published by different philosophers.

Dr Brook Taylor in a paper on magnetism, inserted in the Philosophical Transactions for 1721, describes the result of his trials to determine the weight necessary to separate fir-boards of different sizes from the surface of water. The result of his experiments was,—that the weight necessary is proportional to the surface of the fir-board to be raised.

In the year 1773, Guyton-Morveau ascertained experimentally the force of adhesion of eleven different metals to mercury. The metals which he employed were pure. The surface of each was an inch (French) in diameter, and polished. The following table exhibits the weight in French grains, necessary to separate each metal from the mercury.

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