Johann Christoph Friedrich Bach (1732-1795), the ninth son, was born at Leipzig, studied at the Thomasschule and the university, and in 1750 was appointed Kapellmeister at Bückeburg. He was an industrious composer, especially of church-music and opera, whose work reflects no discredit on the family name.

Johann Christian Bach (1735-1782), the eleventh son, was born at Leipzig, and on the death of his father in 1750 became the pupil of his brother Emanuel at Berlin. In 1754 he went to Italy where he studied under Padre Martini, and from 1760 to 1762 held the post of organist at Milan cathedral, for which he wrote two Masses, a Requiem, a Te Deum and other works. Having also gained some reputation as a composer of opera, he was in 1762 invited to London and there spent the rest of his life. For twenty years he was the most popular musician in England, his dramatic works, produced at the King's theatre, were received with great cordiality, he was appointed music-master to the queen, and his concerts, given in partnership with Abel at the Hanover Square rooms, soon became the most fashionable of public entertainments. He is of some historical interest as the first composer who preferred the pianoforte to the older keyed-instruments; but his works, though elegant and pleasing, were ephemeral in character and have been deservedly forgotten.

A full account of J. C. Bach's career is given in the fourth volume of Burney's History of Music, and a catalogue of his compositions in an article by Max Schwarz, published in the Sammelbände of the Internationale Musik-Gesellschaft, Jhrg. ii. p. 401.

(W. H. Ha.)

BACHARACH, YAIR (1639-1702), German rabbi, was the author of Ḥawwoth Yaīr (a collection of Responsa) and other works. Bacharach was a man of wide culture, and holds an honourable place among the pioneers of the Jewish Renaissance which was inaugurated towards the end of the 18th century.

BACHARACH, a town of Germany, in the Prussian Rhine Province, romantically situated on the left bank of the Rhine, 30 m. above Coblenz on the railway to Mainz. Pop. 2000. There is an interesting church, a basilica, dating from the beginning of the 13th century. There are also ruins of a Gothic church of the 13th and 15th centuries. The ruined castle of Stahleck, crowning the heights above the town, is celebrated in history as the scene of the marriage between Henry, eldest son of Henry the Lion (shortly before the latter's death in 1195) and Agnes of Hohenstaufen, which effected a temporary reconciliation between the houses of Welf and Hohenstaufen. Other ruined castles are those of Fürstenberg and Stahlberg. All three belonged to the counts palatine. The wines of Bacharach were once held in the greatest esteem, and it is still one of the chief markets of the Rhenish wine trade.

BACHAUMONT, LOUIS PETIT DE (1690-1771), French littérateur, was of noble family and was brought up at the court of Versailles. He passed his whole life in Paris as the centre of the salon of Madame Doublet de Persan (1677-1771), where criticism of art and literature took the form of malicious gossip. A sort of register of news was kept in a journal of the salon, which dealt largely in scandals and contained accounts of books suppressed by the censor. Bachaumont's name is commonly connected with the first volumes of this register, which was published anonymously under the title Mémoires secrets pour servir à l'histoire de la République des Lettres, but his exact share in the authorship is a matter of controversy. It was continued by Pidansat de Mairobert (1707-1779) and others, until it reached 36 volumes (1774-1779). It is of some value as a historical source, especially for prohibited literature. Extracts were published by P. Lacroix in one volume, 1859. An incomplete edition (4 vols.) was undertaken in 1830 by Ravenal.

See, in addition to the memoirs of the time, especially the Correspondance littéraire of Grimm, Diderot, d'Alembert and others (new ed., Paris, 1878, 17 vols.); Ch. Aubertin, L'Esprit public au XVIIIe siècle (Paris, 1872).

BACHE, ALEXANDER DALLAS (1806-1867), American physicist, great-grandson of Benjamin Franklin, was born at Philadelphia on the 19th of July 1806. After graduating at the United States Military Academy at West Point in 1825, he acted as assistant professor there for some time, and as a lieutenant in the corps of engineers he was engaged for a year or two in the erection of coast fortifications. He occupied the post of professor of natural philosophy and chemistry in the University of Pennsylvania in 1828-1841 and in 1842-1843. For the trustees of what in 1848 was to become Girard College, but had not yet been opened, he spent the years 1836-1838 in Europe, examining European systems of education, and on his return published a very valuable report. In 1843, on the death of Professor F. R. Hassler (1770-1843), he was appointed

superintendent of the United States coast survey. He succeeded in impressing Congress with a sense of the great value of this work, and by means of the liberal aid it granted, he carried out a singularly comprehensive plan with great ability and most satisfactory results. By a skilful division of labour, and by the erection of numerous observing stations, the mapping out of the whole coast proceeded simultaneously under the eye of the general director, and in addition a vast mass of magnetic and meteorological observations was collected. He died at Newport, Rhode Island, on the 17th of February 1867.