CHROMATIC FRENCH HORN. Since about the be ginning of the 18th century, the attention of different musicians has been turned to the completing of the chro matic scale, or supplying the horn (and trumpet also) with additional notes, both for performing all the notes true in its own fundamental key, and for modulating in to other keys. The late Mr Charles Clagget invented, and took out a patent a short time previous to 1790, and for a time made double horns and trumpets, one of which was tuned half a note lower than the other, and by means of a connected mouth-piece to these tubes, in which there was a valve moveable by the finger, the performer could sound either of these tubes at pleasure, and thus it was pretended that a scale was produced, by some times using one tube and sometimes the other, for differ ent notes; and that the instrument was thus perfected for all the keys in which music is usually written. The fol expressions for the notes of the horn or trumpet in ratios, to the whole length of the tube as unity, and, in our usual notation, will shew the fallacy of these pre tensions, and prove useful on other occasions to the mu sical calculator, viz.
In the column of ratios, the denominators shew the or der in which these 12 notes arise by harder and harder blowing in the same tube ; and the numei ators, as mul tiples of 2, show the successive octaves upwards. in which these notes are produced. In the last column. tne tem peraments or errors of the false notes of horns and trum pets are shown ; thus the 4th of the key of Cis schismas and more too sharp, and the major sixth of the same key nearly 221 schismas too flat, Scc.; whence it is abundantly evident, that no two tubes can mutually sup ply or correct the false notes of the other, as Mr Clag get's invention assumes ; nor will the same succeed any better, in fitting it for transposition or modulation into other keys, as will be easy for any one to try, by adding 612 2412f+53 m to each of these notes in col. 3 for
another octave above this, and then from these, when necessary, deducting the value of the note that is assu med as the new key, and comparing the difference with the perfect intervals in Plate XXX. Vol. II. whence the temperaments, or errors from the respective consonances, will appear for the octave above the new key, as they do in this table for that above C.
French-horns, bugle-horns, and trumpets, have of late been made by Mr Perceval, of St James's Street, with six side finger-holes, as in a flute, for supplying the notes that are false on the common instruments. It is evident, however, that though a considerable approach may be made on such polyphonian or cromatic horns, &c. by the adjustment of the places of the holes on the tube, to a perfect scale in C, or any other key, or even to any assumed tempered scale ; yet it is well known, that modulation cannot be truly effected by help of any 12 notes whatever, except in that most inharmonious of all systems, the equal temperanzent, which no good car could endure to hear in the few trials that have been made of it, much as it is talked and written about. The slide for lengthening or shortening the tube of the trumpet, which Mr Hyde has long used with such good effect in our best concerts, and the regulation of the notes on the horn which the Petrides effect, by thrust ing their hand or a turned block of wood into the mouths of their horns, have not the effect of chromatic trumpets or horns, of which we have been speaking, the scale consists of half-tones only; but by this management they become perfect instruments, (com bined with the crooks that the latter use in different keys,) on which they can effect any of the small changes, for producing perfect harmony with the other notes of the piece, as on violins, voices, and Mr Liston's organ. (c)