A discussion of a subject so difficult and complicated is not easy to follow. It is but just to other investigators, and fair to the reader, to present the views of those who have possessed special qualifications for dealing with the questions involved. The author will endeavor to present the grounds on which others have taken their stand, in a few words and clearly, if the reader will patiently follow. There will at first seem, possibly, to be little agreement, but it will be shown that on some of the most essential points there is substantial unity of opinion; and the subject is of such vital moment, as the author will endeavor to make clear, that it is hoped that the most patient examination will be given to the questions that arise, from the beginning to the end of the discussion. For the author to express a dogmatic opinion, and simply state his disagreement or agreement with others, would be contrary to the whole spirit of this work, and leave the subject where it once was--in the realm of hopeless disagreement and controversy. If the problem of the registers is to be solved to the satisfaction of the rational thinker, it must be by evidence, and not the mere opinions of any teacher or writer, however eminent. To lay this evidence before the reader is now the author's task. One of those most eminently equipped, by a great variety of qualities, for the investigation of this subject, or any other question of the voice, was Madame Seiler. Whenever the author is obliged to differ from this really great investigator, he does so with the sense of the highest respect for her opinions generally, because she always sought for scientific grounds for such opinions. Her views may be thus briefly presented: She recognized three registers, chest, falsetto, and head, with their subdivisions. (1) The first chest register extends (1) The whole glottis (vocal to [Illustration: a b-flat] in men, bands) is moved in loose and to [Illustration: c' c-sharp'] vibrations. in women. (2) The second chest register extends (2) The vocal ligaments (or to [Illustration: f' f-sharp'] in both ligamentous glottis) alone sexes. are in action. (3) The first falsetto extends in (3) The edges alone of the females to [Illustration: c'' c-sharp''] vocal bands vibrate, but the and in males to [Illustration: e'' whole glottis is in action. e-flat'']. (4) The second falsetto in the (4) The edges only of the female extends to [Illustration: vocal bands are used, and the f'' f-sharp''] and to [Illustration: g''] vocal ligaments alone are in in women. action. [Transcriber's Note: So in original; "female" should probably be "male."]