HERSCHEL KERTHA HERSCHEL, SIR JOHN FREDER- ICK WILLIAM, an English astronomer and physicist; only son of Sir William Herschel; born in Slough, near Windsor, England, March 7, 1792. In 1813 he graduated at Cambridge. He spent eight years reviewing the nebulae and clusters of stars discovered by his fa- ther. The results were given in 1833 to the Royal Society in the form of a cata- logue of stars. In 1830 he produced his excellent " Preliminary Discourse on the Study of Natural Philosophy." In 1834 he established, at his own expense, an observatory at Feldhuysen, near Cape Town, Africa. He returned to England in 1838 and in 1847 published " Results of Astronomical Observations made dur- ing 1834-1838 at the Cape of Good Hope, being the Completion of a Telescopic Survey of the Whole Surface of the Vis- ible Heavens." He was one of the earli- est pioneers in photography; and on the queen's coronation he was created a baronet. Among his other works aro " Outlines of Astr'onomy," " Familiar Lectures on Scientific Subjects," and a translation of the Iliad in verse. He died May 11, 1871. HERSCHEL, SIR WILLIAM, an English astronomer; born in Hanover, Prussia, Nov. 15, 1738. The son of a musician, he went to England in 1757, and was employed in the formation of a military band. He had for some time devoted his leisure hours to the study of mathematics and astronomy; and, be- ing dissatisfied with the only telescopes within his reach, he set about construct- ing instruments for himself. Late in 1779 he began a regular survey of the heavens, star by star, with a 7-foot re- flector, and discovered, March 13, 1781, a new primary planet, named by him the Georgium Sidus:. This discovery ex- tended his fame throughout the world and brought him a pension of £200. He then took up his residence at Datchet, near Windsor, where he made many dis- coveries in double and triple stars, on the proper motion of the sun and solar system, the spots at the pole of Mars, and the nebulae and cluster of stars ob- served by Messier and Mechain. In 1787, he discovered a 2d and 4th satellite of the Georgium Sidus, and in 1790 and 1799, five other satellites, viz., the 1st, 3d, 5th, and 6th. In 1781, George III. defrayed the expense of a 40-foot tele- scope. With this magnificent instru- ment Herschel discovered the 6th and 7th satellites, and also the spots belts, and flattening on the four new planets between Mars and Jupiter. We owe to him also the discovery of invisible heat- ing rays beyond the red extremity oi the spectrum. In 1820 he was elected the first President of the Royal Astro- nomical Society, and published in the first volume of its " Transactions " a paper on 145 new double stars. He died la Slough, near Windsor, England, Aug 25, 1822. HERSCHELIAN RAYS, non-lumi^ nous rays outside the red of the solar spectrum; they were first discovered by Sir William Herschel. HERSCHELITE (named after Sir John Herschel), an orthorhombic, color- less or white translucent mineral of somewhat vitreous luster optically biax- ial. Found at Acireale in Sicily. HERSTAL, or HERISTAL, a city of Belgium in the province of Liege. It is on the left bank of the Meuse river. It is an important iron and steel center and has munition works, manufactures of bicycles, etc. In the vicinity are im- portant coal mines. Pop. about 23,000. HERTER, ALBERT, an American artist, born in New York City in 1871. He studied in New York and in Paris, received honorable mention in the Paris Salon in 1890 and several medals and prizes for excellency in painting. He was especially eminent as a mural painter and was a member of many art and architectural societies. HERTFORD, the county town of Hertfordshire, England, 26 miles N. of London; on the Lea river. It contains few buildings of any architectural im- portance, save one ancient church; but there is a town hall (1768), and on London Road is a preparatory school in connection with Christ's Hospital, Lon- don. A considerable trade is carried on in corn, malt, and flour. Of the old castle of Hertford, commenced by Ed- ward the Elder about 905 to protect the inhabitants from the incursions of the Danes, and strengthened by William the Conqueror, only a small portion now re- mains. Pop. (1918) 10,384. HERTFORDSHIRE, a county of Eng- land, bounded on the E. by Essex, on the S. by Middlesex, on the W. by Buckingham and Bedford, and on the N. by Cambridge. It has an area of about 630 square miles. Agriculture is the chief industry. The capital is Hertford. HERTHA, the goddess of Earth, wor- shiped by the ancient Germans. In as tronomy, an asteroid, the 135th found It was discovered by Peters, Feb. 18, 1874.
