EUSTATHIUS EVAPORATION. 



113 



published till a much later period. The text ha 

 never been found. Albinus published an excellent 

 commentary on these tables (Leyden, 1743, fol.). 

 Another of his works, De Anatomicorum Controversiis, 

 is also lost. Besides these, we liave many other 

 valuable works by him. Boerhaave published an 

 edition of them at Leyden, 1707, which was reprinted 

 at Delft, 1736. Eustachi died at Rome, 1574. 



EUSTATHIUS, a commentator on Homer and 

 the geographer Dionysius, originally a monk, after- 

 wards deacon, and finally, 1155, archbishop of 

 Thessalonica. He died after 1194. Though not 

 very enlightened in his theological views, he was 

 deeply read in the classics, and a man of extensive 

 erudition, as appears from his commentaries compiled 

 from the old scholiasts, of which tliat on Homer, in 

 particular, is an inexhaustible mine of philological 

 learning (Rome, 154250, 4 vols. fol., and Bale, 

 1559 go, 3 vols. fol., new edition Leipsic, by Weigel, 

 commenced in 1825., 4to). 



EUSTATIA, ST, one of the Leeward islands, 

 fifteen miles south-east of Saba, and eight north-west 

 of St Christopher's, is a huge rock, rising- out of the 

 waves, in the form of a pyramid, twenty-nine miles in 

 circumference. Sugar, cotton, and maize are raised 

 here ; but the principal production is tobacco, which 

 is cultivated on the sides of the pyramid, to its very 

 top. There is but one landing place, and that, 

 though difficult of access, is strongly fortified. The 

 number of inhabitants is 18,000, of whom 4000 are 

 whites, chiefly Dutch, and 14,000 negroes. The 

 Dutch made the first settlement on this island about 

 the year 1600. In the year 1665, it was captured 

 by an English expedition. The French, however, 

 soon afterwards expelled the British, and restored it 

 to the Dutch in 1667. The English retook it in 

 1689, and restored it on the termination of the war in 

 1697. In 1781, a large naval and military force, 

 under admiral Rodney, compelled the inhabitants, 

 who were incapable of defence, to submit at discre- 

 tion. The English commanders, under the pretence 

 that the people of the island had supplied the United 

 States of America with naval stores, confiscated all 

 private property, and, at one blow, reduced the 

 unfortunate inhabitants to poverty. In the same 

 year, however, the island was retaken by a small 

 body of French troops, under the command of the 

 marquis de Bouille. St Eustatia was again attacked 

 by the British in 1809, and compelled to submit; 

 but, in 1814, the Dutch government was restored. 



EUTERPE ; one of the muses, considered as 

 presiding over music, because the invention of the flute 

 is ascribed to her. She is usually represented as a 

 virgin crowned with flowers, having a flute in her 

 Jiand, or with various instruments about her. As 

 her name denotes, she is the inspirer of pleasure. 

 See Muses. 



EUTHANASIA; a gentle, easy, happy death. 

 Wieland gave this name to one of his works. 



EUTROPIUS, FLAVIUS ; a Latin historian, who, 

 as he himself informs us, bore arms under the 

 emperor Julian. The place of his birth and his 

 history are unknown to us. He flourished about 

 360 A. D. His abridgment of the history of Rome 

 (Brevtarium Historic Romance) reaches from the 

 foundation of the city to the time of the emperor 

 Valens, to whom it is dedicated. The style, though 

 not finished, is perspicuous. The most esteemed 

 editions are those of Havercamp (Leyden, 1729), 

 Verseik (Leyden, 1762, 2 vols.), and Tzschucke 

 (Leipsic, 1804.) 



EUXINE (Pontus Euxinus); the ancient name 

 for the Black sea. 



EVAN ; a surname of Bacchus. See Bacchus. 



EVAPORATION is the conversion of liquid and 

 in. 



solid bodies into elastic fluids, by the influence of 

 caloric. Expose, for instance, water to heat, bubbles 

 at first adhere to the sides of the vessel, which, by 

 degrees, ascend to the surface, and burst. These 

 bubbles rise the more rapidly in proportion to the 

 heat. Water is evaporated by the heat of the sun 

 merely, and even without this in the open air, and 

 the vapour, rising into the air, is condensed into 

 clouds. The general cause of evaporation is caloric ; 

 but different substances require different degrees of 

 it. Water is particularly subject to evaporation. It 

 evaporates at a very low temperature, and, from the 

 immense quantity which is spread over the earth, it 

 may be inferred, with great probability, that the most 

 important clianges in our atmosphere are occasioned 

 by it. Instruments have been invented to measure 

 the evaporation of water (see Atmomnter), but the 

 results are uncertain. If we assume, as experiments 

 justify, that the annual evaporation averages thirty 

 inches (i. e. that the vapour, if reconverted into 

 water, would cover the surface from which the 

 evaporation took place, to a height of thirty inches), 

 then, the surface of all the waters on our earth 

 being assumed at 128,000,000 of geographical miles, 

 60,000 cubic miles of water, would be annually chang- 

 ed into vapour ; and the amount will be still greater, 

 if we add to it the evaporation from moist earth, and 

 from the watery parts of the vegetable and animal 

 kingdoms. In summer, evaporation is generally 

 much greater than in winter ; yet it is not so incon- 

 siderable in cold weather as we might suppose from 

 the small quantity of caloric then sensible. Even 

 in the polar circles, it does not entirely cease ; for 

 ice evaporates in the open air. To account for the 

 phenomenon of evaporation, two hypotheses have 

 been formed; that it is a conversion of fluids into 

 elastic vapour by their union with caloric, or that it 

 is a real solution of the fluids in the air. The latter 

 theory has been opposed, particularly by De Luc. 

 He maintains that in evaporation, water combines 

 with caloric, without being dissolved in the air. The 

 principal argument in support of this theory is, that 

 cold is generated by the evaporation of a liquid. 

 Cold is only the absence or consumption of caloric. 

 If now, in evaporation, caloric is consumed, i. e., 

 is combined with the evaporated water, this 

 consumption must generate a sensible cold. De 

 Luc further maintains, that the air, so far from 

 contributing to evaporation, prevents it by its pres- 

 sure. If this pressure is removed, the same quantity 

 of water requires far less caloric to evaporate it ; for 

 experiments show that water evaporates more rapidly 

 in a vacuum than in the air, and Saussure says, that, 

 at the same degree of the thermometer and hydro 

 meter, the evaporation on mountains, where the air is 

 of three times less density, is more than double that 

 in the valleys. Later experiments render it still 

 more evident that a dissolving- power of ah- is not 

 necessary to change water into an elastic vapour, 

 since, otherwise, it could not be produced in a va- 

 cuum. Sucli a dissolving power in the air, however, 

 is absolutely required to eliect a uniform mixture of 

 this vapour with air ; otherwise, from the difference 

 of the specific gravities of the two fluids, a separation 

 must ensue, of which we have no experience ; and 

 we find ourselves compelled to regard the union of 

 the expansive vapour with the air as a true solution 

 of the one in the other. De Luc developed the first 

 view in the Nouvelles Idees sur la Meteorologie (Lon- 

 don, 1786, 2 vols.), while the solvent power was 

 maintained to be the cause of evaporation by Hube, 

 in his treatise on Evaporation (Leipsic, 1790). See 

 Perspiration. 



Artificial Evaporation is a chemical process, usually 

 performed by applying heat to any compound sul>- 



