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 ASTRONOMY ASTUEIAS suns, many closely resembling our sun in ele- mentary constitution, others formed very dif- ferently, but all incandescent orbs as he is, and surrounded by the glowing vaftors of many ele- mentary substances. The application of the analysis to nebulae has led to the surprising dis- covery that while many of these objects shine with a light resembling that of our own sun, so that they may be considered to be formed by the aggregation together of many stars, others consist almost wholly of glowing gas, nitrogen and hydrogen forming their chief con- stituent elements. The observations of recent solar eclipses have been rewarded by many interesting discoveries respecting the physical constitution of the sun, the colored prominences surrounding him, and the corona which lies be- yond the prominences. In these discoveries, Huggins, Young, Janssen, Lockyer, Eespighi, and Secchi have borne the principal part. The progress of practical astronomy, and par- ticularly the application of the telescope to the determination of the exact position of the celestial bodies, has proceeded pari passu with the progress of mathematical analysis and di- rect telescopic observation. The invention of the equatorial, the transit instrument, the mu- ral circle, and other instruments of exact obser- vation, belongs to the comparatively early his- tory of modern astronomy. In the present day these instruments are constructed with a degree of perfection, and with a multiplicity of contrivances for improving their performance or extending their application, which are truly surprising. Nor have the achievements of in- strumental astronomy fallen short of the prom- ise afforded by the qualities of the instruments. It would be sufficient to point out that the telescope has revealed the greater number of those minute inequalities of planetary motion which have afforded the material for the ana- lytical researches above referred to; but we may add that we owe to the telescope the recognition of the aberration of light, the dis- covery of the proper motions of the stars, the determination of the sun's distance, and the partial solution of the most difficult problem yet attacked by astronomers, the determina- tion of the distances of the stars. Lastly, the spectroscope promises to play an impor- tant part in instrumental researches, since already it has been applied to the determi- nation of the velocity with which stars are approaching us or receding from us, and to the measurement of movements taking place within the solar atmospheric envelopes. For a popular view of astronomy, Sir John Her- schers "Outlines" may be recommended; and full details respecting practical astronomy will be found in the treatise on that subject by Prof. Loomis of New York, justly described by Prof. Nichol as "the best work of the kind in the English language." A thorough knowledge of physical astronomy would require an acquaint- ance with such works as Laplace's Mecanique celeste, translated by Bowditch, Gauss's The- 66 VOL. ii. 4 oria Motus Corporum Ccelestium, translated by Admiral C. H. Davis, U. S. N. (Boston, 1858), Delambre's Astronomie, orPeirue's "Analytical Mechanics " and "Celestial Mechanics." For the history of astronomy, see Whewell's " His- tory of the Inductive Sciences," Grant's "His- tory of Physical Astronomy," Jahn's Geschichte der Astronomic, and Delambre's Histoire de Vastronomie. For full information concern- ing the modern history of astronomy, Zach's Monatliche Correspondenz, Lindenau's Zeit- sclirift, Schumacher's AstronomucJie NacJiricJi- ten, continued by Dr. Peterson, and Gould's " Astronomical Journal " (Boston) must be consulted; also, the French Connaissances des temps, which contain Leverrier's discussions that led to the discovery of Neptune, the Berlin Jahrbuch, the Milan Effemeridi, and the Amer- ican " Ephemeris and Nautical Almanac." ASTRIIC, Jean, a French physician, born at Sauve, March 19, 1684, died May 5, 1766. He was a graduate and became a professor of the medical college of Montpellier as a substitute of Chirac, on whose death he succeeded him in the professorship, after having filled for some time the. chair of anatomy in Toulouse. In 1730 he became regent and professor of the faculty of medicine at Paris, and was also phy- sician to the king. His most celebrated work is De Morlis Venereis Libri sex (2d ed., 2 vols., 1740; translated into French and other languages) ; and he was regarded as a high authority on venereal and female diseases and obstetrics, though he excelled rather by his prodigious memory than by inventive genius. Among his many other writings are Traite des maladies des femmei (6 vols., 1761 '5), and a posthumous work, ISart d'aeeoucher reduit a ses principes (1 vol., 1768). ASTIJRIAS, a former province of N. W. Spain, bordering on the bay of Biscay, bearing the title of principality, and still commonly known by its ancient name, although since 1833 it constitutes the province of Oviedo ; area, 4,088 sq. m. ; pop. in 1867, 588,031. The surface is irregular and hilly, the country being intersect- ed by offshoots of the Cantabrian mountains, a chain varying in height from 6,000 to 10,000 feet. The scenery is picturesque and wild, and the coast is almost everywhere bold and high. The rivers are few and generally unimportant, the Nalon being the chief. The province is rich in coal, and in the north many mines are worked ; the coal is shipped from Aviles and Gijon. Maize, wheat, potatoes, and fruits are the chief productions. The horses of Asturias are celebrated for strength and endurance. The inhabitants are of simple habits, retaining many old Spanish customs and peculiarities of dress that have elsewhere disappeared. They are proud of the freedom of their race from the admixture of Jewish and Arab blood found in the other provinces, and affect a superiority to other Spaniards. The herdsmen (raqueros) among them form a separate and nomadic class, spending the winter on the coast and the sum-