But there is a description of these cartilages by Dr. Witkowski which corresponds very closely with Madame Seiler's. Speaking of some of the glands of the voicebox, he says in the work mentioned before, on p. 12--"They are arranged in the form of an L, whose vertical branch goes along the arytenoid cartilages (the pyramids), _the horizontal branch following the direction of the vocal cords_. _There is often found situated in the midst of this group of glands the cuneiform cartilage of Wrisberg_, sometimes reduced to a mere cartilaginous granule." Dr. Elsberg also describes them on p. 37 of the treatise before mentioned as "elongated nodules" in the hinder portion of the vocal ligaments, and says they are found "more often in the female than in the male sex." He calls them the "posterior vocal nodules," and gives on p. 36 a diagram which shows them most clearly and unmistakably. This point would therefore seem to be settled. =The Resonator.=--We now come to the last part of our instrument, namely, the resonator, which is formed of (1) the pockets of the larynx; (2) the tube above the pocket ligaments; (3) the upper part of the throat; (4) the mouth; and (5) the nose. Before giving a description of the resonator, it will be necessary to make a few introductory remarks on certain laws of the philosophy of sound, which have been so clearly demonstrated that they admit of no contradiction. =Tone=, as we have seen, is the result of rapid periodic vibrations. The =Loudness= of tone depends upon the _amplitude_ of the vibrations. This is easily shown by drawing a bow over the string of a violin: while the vibrations of the string are largest, the tone produced is loudest, and as the vibrations get smaller, so the tone becomes fainter. The =Pitch= of tone depends upon the _number_ of vibrations in a given period of time. The greater the number of vibrations the higher the pitch, and _vice versa_. The =Quality= of tone depends on the _form_ of the vibrations, "which also determines the occurrence of upper partial tones."[K]