FINGER-KEYED INSTRUMENTS, in Music, are in gene ral such as are performed upon by touching with the fin gers a system of of levers, called keys, manual keys, or the clavier. The organ, virginal, spinet, harpsichord, piano forte, and barillons or carillons, are well known in this class of instruments. Mr John Isaac Hawkins, a few years ago, invented a new instrument, consisting of a rotative bow of horse hair, that could be made to act at pleasure upon cat gut strings, which he denominated a Finger-keyed vial or claviole. M. Chladni likewise invented a new instrument, called a Keyed Cylinder. See the Monthly Magazine, vol. xxviii. p. 514.
The ordinary form and arrangement of Finger-keys, are found well adapted to the diatonic scale, or that in which five notes and two half notes are comprised in the octave, two whole notes or long keys being associated together, and three such, with a half tone between each of these groups, which are separately called a ditone, and a tritone, by Dr Callcott. In the former of these groups, two shorter keys of a different colour (now usually black, the long keys being white,) are inserted between the long ones ; and, in the tritone, two short keys are interposed, by which the whole douzeave, or range of 12 half notes in the octave, is completed, and every other octave, above and below, is but a repetition of the first.
The most conspicuous and best marked finger key in the arrangement above described, is the long one in the middle of the ditone, which belongs to the letter D, which is the second of the natural key ; beginning therefore at C, the letters belonging to each of the finger keys are as fol lows : viz.
Although three of the short notes above are described as sharps, and two of them as fiats, yet common instruments are obliged to be so tuned, that every short note may in discriminately serve either for the sharp of that on its left hand, or for thefat of that on its right, and even so that E and F, and B and c, may also serve as the flats or sharps of each other respectively.
This very confined nature of the key-board, or system of finger-keys, long presented a serious bar to improvement in the tune of these instruments with fixed tones, until at length Mr Hawkes produced his patent instruments, on which all the five short notes might be tuned to sharps, and, by means of a pedal, the connection of the keys with these strings or pipes might be instantly loosed, and the same short keys be made to act on another set of those tuned to fiats, thereby introducing 17 sounds in the octave, but with the disadvantage of being unable to use a flat of any one note and a sharp of another at the same time. But these and other defects the patent instruments of M. Loeschnian and of Mr Liston now remedy, by means of se veral pedals, adapted to take away two sharps at a time at one end of the scale, (See our article Succession of Fi rens), and to supply to the same finger-keys two flats in the place of them, in the order of modulation : thus, for instance, out of the original scale that we have represented above, the first flat pedal will remove G and CgC, and supply in their places AI, and DI, ; the first sharp pedal will remove Eb• and B [7, and replace their connection with the short finger keys, by Di4 and Ai4, and so on, leaving the performer all the present uses of the finger-keys, except during the in stants when the pedals are in motion.
However perfect and easy the use of the present key board may seem to practised musicians without the pedals above mentioned, a desire has long existed for simplifying it for the use of children and beginners. This the late Mr Charles Clagget attempted by his equal keys ; and more re cently Mr Trotter took out a patent for a key-board, bet ter adapted to the use of beginners, and for transposing or playing music in a different key from that in which it may be written. See the details of this latter invention in the Repertory, vol. xxii. p. 197. FINGER-KEy Intervals, in Music, or degrees of the stave or scale, are very commonly denominated half-notes, half-tones or semitones, and considered as equal among them selves! as though the Isotonic system was alone in use, notwithstanding the high probability, which has often been mentioned, that an equal temperament has never yet been heard on the organ, rarely so (or very near it) on the piano forte ; and it is certain that this system never was, or tvill be, performed by the voice or violin. It is, however, of considerable use to the musical student, to be able to class the great number of musical intervals which present them selves according to the finger-key of his organ to which they severally belong, and by which they can alone be brought into use on that instrument, while the key-board remains limited as at present. Fortunately, the new nota tion which we use, enables us to make this classification without any trouble, because every interval, regularly ex pressed in Farey's Notation, (Sec that article), has the f's therein equal to its number afinger-key intervals, artificial half-notes, chromatic semitones of Callcott, as the fol lowing table will fully explain, viz.
This Table has three columns, numbered at the top and titled at the bottom, the first of which spews the number of I's, in the least interval that has 1, 2, 3, &c. f's respec tively, in col. 2 ; or, such M's in col. I. may be considered as the limits between the different finger-keys numbered 1, 2, 3, &c. in col. 2. In col. 3, sometimes 3 and some times 4 intervals, numerally expressed with the addition of b's and are set down as belonging to each finger-key; such pairs of these intervals as are linked together, are of equal value, respectively, in Mr Liston's enharmonic scale. Each of the finger-keys on Mr Liston's organ, yield occa sionally five different sounds, except the ninth, or A key, which produces only four sounds, making in all 59 sounds in the octave. (c)