ABSTRACT
Throughout the world the truth and glory of the science of the art of music, upon which the foundation of the universal Church rests, and which manifestly endures since its creation along with the angels, has vanished and lies virtually prostrate. It is to be understood that the art of music is satisfied with a sevenfold number of letters: A, B, C, D, E, F, G (according to a similitude, for there are seven gifts of the Holy Spirit, of whose species this science is one). It remains for us to come to the knowledge of the hand and through it to the "key" that opens the science of the art of music. If someone ignorant of music should presumptuously attribute to one of the tones more notes and letters, those letters and notes are according to its nature utterly superfluous.
