SECT. X.
XXXIX. Some (for we would not omit to mention this) judge, that the composing music adapted to different subjects, consists much, in a right choice of the keys; and they assign one for grave subjects, another for chearful ones, and another for mournful ones, and so on; but I believe, this contributes little or nothing to the business; for there is no key whatever, in which there have not been written, very expressive and pathetic compositions, suited to excite all kinds of affections. The different place which the two semi-tones occupy in the diapason, and which is what the distinction of keys consists in, is insufficient to induce this diversity; because in whatever place an accidental is introduced, and they introduce them at every turn, this order is changed; and because various, or the most parts of the composition, by varying their terminations, fall upon, or catch the semi-tones, in a different position, from that in which they stand or are placed, with respect to the diapason. For example; although the first key-tone, which begins D solre, proceeds in this order, first a tone, then a semi-tone, after that three tones, to which there follows another semi-tone, and at last there comes a whole tone. The different traces, or minute passages of the composition, taken each by itself, do not follow this order; because one begins in the first, another in the tone which is next after it, and so on with respect to all the other parts of the diapason, and they terminate wherever the composer likes best; by which means, in every trace or minute passage of the composition, the position of the semi-tones is varied, as much, as in the different diapasons, which constitute the diversity of the keys.
XL. What confirms me in this sentiment, that the suiting music to produce a grave or a sprightly effect, does not depend upon the choice of the key it is wrote in, is, that the greatest musicians, are much divided in their opinions upon this point. What one considers as a lively key, another thinks a mournful one; what one esteems a devout key, another calls a flighty one. The two great jesuits, father Kircher, and father Dechales, are so opposite in their sentiments upon this head, that the same key, which father Kircher characterizes in this manner, Harmoniosus, magnificus, & regia majestate plenus, father Dechales speaks thus of: Ac tripudia, & choreas est comparatus, diciturque propterea lascivus; and they differ little less, in their assignation of the characters of many other keys, if not of all.
XLI. The foregoing, should be understood to relate and apply to the essential difference of keys, which consists, in the diversity of position of the semi-tones in the diapason; but not to their accidental difference; which, consists, in their being taken higher or lower. This may conduce something to create effect; because the same music, set in low notes, which is religious and grave, transposed to high ones, loses of its majesty, and acquires a degree of vivacity, that is ill suited to a solemn subject: and for this reason, I am of opinion, that the movements of church music should not be very quick: because, by hurrying the voices in the chant, they occasion them to sound harsh; and besides this, prevent that easy play and flexibility of throat, which is necessary to produce the effect the music requires; and which many times consists, or is contained in the intonations; I say further, that over and above these inconveniences, music composed of quick movements, and set in high notes, is not so well calculated to move the affections of respect, devotion, and piety, as that which is written in lower tones, and marked to be performed in slower time.