of Santa Maria della Salute in Venice, and in that of the Annunciation at Genoa, the latter from about 1750 till his death. His principal operas are 'L'Artaserse,' 'L'Arianna,' 'Adriano in Siria,' and 'La Gloria ed il Piacere,' the first produced in Rome in 1742, the three last in Genoa in 1750–1752. He left also sacred compositions, chiefly Psalms. 'Arianna' is said to contain an air in the measure of five beats to the bar.
ADRIEN, or ANDRIEN, Martin Joseph, called Adrien l'Ainé, born at Liége 1766; a bass singer, taking alternate parts with Chéron at the opera in Paris from 1785 to 1804; afterwards choirmaster at the opera. In March 1822 he succeeded Lainé as professor of declamation at the École Royale de Musique, and died in the following November, a victim to the exaggerated system of declamation then in vogue. His voice was harsh, and his method of singing bad, but he had merit as an actor. He composed the 'Hymne à la Victoire' on the evacuation of the French territory in 1795, and the hymn to the martyrs for liberty.
His brother (name unknown) was born at Liége 1767; published five collections of songs (Paris, 1790-1802), and was for a short time choirmaster at the Théatre Feydeau.
Another brother, Ferdinand, was a teacher of singing in Paris, choir-master of the opera (1799-1801) and composer of songs.
A DUE (Ital., 'In two parts'), or A 2. This expression is used in two exactly opposite ways in orchestral scores. For the wind instruments, for which two parts are usually written on the same stave, it indicates that the two play in unison; for the strings, on the other hand, it shows that the whole mass, which usually plays in unison, is to be divided into two equal parts, the one taking the upper and the other the lower notes. In practice there is never any difficulty in seeing which meaning is intended.
AELSTERS, Georges Jacques, born of a musical family at Ghent, 1770, died there 1849; carilloneur of that town from 1788 to 1839; for fifty years director of the music at the church of St. Martin, and composer of much church music still performed in Flanders, especially a 'Miserere.'
AENGSTLICH (Germ, 'fearfully'). A word which calls for notice here only on account of its use by Beethoven at the head of the recitative in his Missa Solennis, 'Agnus Dei, qui tollis peccata mundi, miserere nobis.' In this most dramatic and emotional part of his great work Beethoven seems to realise the 'prayer for internal and external peace' which he gives as a motto to the entire 'Dona': the fierce blasts of the trumpets alternating with the supplications of the voices bring before us the enemy at the very gates. As in the case of Accelerando Beethoven has accompanied the German word with its Italian equivalent tramidamente.
ÆOLIAN HARP. (Fr. La Harpe Æolienne; Ital. Arpa d' Eolo; Ger. Æolsharfe Windharfe.) The name is from Aeolus the god of the wind. The instrument, of which the inventor is unknown, would appear to owe its origin to the monochord, a string stretched upon two bridges over a soundboard. The string happening to be at a low tension and exposed to a current of air would divide into various aliquot parts according to the varying strength of the current, and thus give the harmonics or overtones we hear in the music of this instrument. Had the principle of the Æolian harp never been discovered, we should in these days of telegraphy have found it out, as it is of frequent occurrence to hear musical sounds from telegraph wires which become audible through the posts which elevate the wires, and assume the function of soundboards. Once recognised on a monochord, it would be a simple process to increase the number of strings, which, tuned in unison, would be differently affected in relation to the current of air by position, and thus give different vibrating segments, forming consonant or dissonant chords as the pressure of wind might determine. That musical sounds could be produced by unaided wind has been long known in the East. According to tradition King David's harp (kinnor) sounded at midnight when suspended over his couch in the north wind; and in an old Hindu poem, quoted by Sir William Jones, the vina, or lute of the country is said to have produced tones, proceeding by musical intervals, by the impulse of the breeze. In the present day the Chinese have kites with vibrating strings, and the Malays have a curious Æolian instrument, a rough bamboo cane of considerable height, perforated with holes and stuck in the ground. This is entirely a wind contrivance, but they have another of split bamboo for strings. (C. Engel, 'Musical Instruments,' 1874, p. 200.) St. Dunstan of Canterbury is said to have hung his harp so that the wind might pass through the strings, causing them to sound, and to have been accused of sorcery in consequence. This was in the 10th century. It was not until the 17th we meet with the Æolian harp itself. Kircher (1602-1680) first wrote about it. He speaks of it in his 'Musurgia Universalis' as being a new instrument and easy to construct, and as being the admiration of every one. He describes the sounds as not resembling those of a stringed or of a wind instrument, but partaking of the qualities of both. This is quite true, and applies to any stretched string the sound of which is made continuous by any other agency than that of a bow, and not dying away as we usually hear the tones of pianofortes, harps, and guitars. Thomson, in the 'Castle of Indolence,' in well-known lines, describes the Æolian harp, but except one phrase, 'such sweet, such sad, such solemn airs divine,' misses the elegiac note that distinguishes the instrument. Matthew Young, bishop of Clonfert, in his 'Enquiry into the Principal Phenomena of Sounds and Musical Strings' (1784), gives full particulars of it, and
