KEY, IN Music, is a term ambiguously used by most practical musicians. Sometimes by this term they mean a scale or system of intervals; at others, it implies the lowest or fundamental note of the system, as above ; and, on other occasions, this term also designates one of the short levers on which the fingers act, in performing on organs, piano-fortes, Ste. Writers, who have aimed at greater precision in their terms and writings, have made the following distinctions, viz.
KEY note, called formerly ison or mese, the fundamen tal or bass note of every mode or scale of intervals, as above ; each tune, or piece of music, usually begins with its key-note, and invariably ends with it; otherwise, as experience has shewn, the ear would not be satisfied, or the subject of the tune seem closed and ended. The moderns consider C as the principal or first key of the major mode ; and by a series of modulations into its suc cessive or consecutive fifths, above and below, they derive all the other key-notes. Mr. Liston first shelved how this modulation could be conducted, without departing from the harmonic relations of the first key-note, or C, by re turning often to one of the consecutive ads or 6ths of this first key-note ; and thus he extended the scale to 59 notes in the octave ; and Mr. Farey has now extend ed the same to 612 notes. See our article INTERVALS.
KEY, or Mode, implies a system, or scale of intervals. The practical, and less correct writers on music, have often asserted, that a key or mode, whether major or minor, consists only of seven sounds, which, in the first or principal key, or mode major, are C, D, E, F, G, A, and B ; and in the principal minor key, or note, are A, B, C, D. E, F, and G ; but Mr. Liston, in pp. 59 and 61 of his Essay, chews that the major mode C is not complete, or capable of correct or enharmonic performance in it, (such as violins and voices actually accomplish,) without 10 notes instead of 7; viz. C, D', D, E, F, F, G, A, A', and B. In like manner, in pp. 64 and 67, he slims that the first or principal minor mode or key A, requires also 10 notes, viz. A, B, C, D, D, E, F, F, G, and G.
Combining, therefore, these two scales together, it thus appears, that 12 notes are required instead of 7, as some still inconsiderately assert, for simply accompanying, or producing the harmonics to an ascending and descending bass octave, in the modes C major and A minor. It need,
therefore, excite no surprise, that in modulating through all the keys or modes in use, so many as 59 notes become aecesssary ; but rather, how so few notes should suffice, which is owing to so many of the notes answering in various keys.
Finger-KEYs, manual-keys, or clavier, are the short levers of the keyed instruments, by means of which they are played upon ; usually there are 12 of these to each octave of the compass or extent of the instrument ; seven of them longer and broader than the other five, which are shorter and narrower, and stand ttp higher between the longer keys ; according to the arrangement which is ex plained in our article FINGER-Keyed Instruments.
The organ in the Temple church in London has two of its short keys divided in their lengths, so as to produce two distinct levers or keys, by which means the fingers can act occasionally on 14 notes in each octave, instead of 12 ; we have read, or heard, of attempts formerly to di vide more of the keys, one as early as 1683, by a Mr. Player, and thus to multiply the powers of the fingers in performance, as to improved harmony ; but so many diffi culties, and liabilities to mistakes, in the hurry of per formance, were thereby introduced, that we believe tnese divided finger-keys no where remain,in use, except two of them in the Temple organ scale, as already mentioned.
The late Dr. Robert Smith supplied the place of more finger-keys, in his harpsichord, by stops, to be moved by the hand, which put some notes out of action by the ordinary 12 finger-keys, and brought others into action in their stead ; and this mode remains yet in use in the Foundling-hospital organ in London, for four additional notes ; but, within a few years past, Mr. Hawkes, and, since him, Mr. Loeschman!and Mr. Liston have effected these occasional shillings of the notes, belonging or attached to the oroinary finger-keys, by means of pedals, or short levers, to be moved by the feet of the performer, which seems an improvement of very considerable importance in the practice of instrumental music. In March 1811. John Trotter, Esq. took out a patent for finger-keys of equal width throughout, in two ranges, for facilitating the trans position of music into any key, during its performance, as may be seen in the second series of the Repertory of Arts, vol. xxii. p. 197.