The author examined with the laryngoscope 50 persons, who might (with Gruetzner) be divided into "trained singers," "natural singers," and "non-singers." The whole glottis was found to be open in all voices in the lowest tones of the chest register, and this condition obtained up to about [Illustration: f-sharp' g'], beyond which another mechanism came into play, except in rare cases. The high falsetto of men and the head voice of women are produced by a similar mechanism and method. In the investigation of registers more attention should be given to the use of the breathing organs than has hitherto been done by those writing on this subject. As Madame Marchesi, of Paris, has taught with preeminent success, and with the greatest practical consideration for the preservation of the voice and the vocal organs in an unimpaired condition, and as the author has had, through her kindness, the opportunity to become acquainted with her methods by observation, her views on the registers are here presented. It is to be understood that as she teaches only ladies, her views are considered, so far as she is concerned, as applying only to female voices. These views are further presented because Madame Marchesi was herself taught by Garcia, who was in the direct line of the old Italian masters, though it will be observed that the pupil has retained only the essentials of the master's views on the registers. 1. There are three registers in female voices: chest, middle, and head. 2. While there are small differences in voices and individuals as regards the registers, the following principles apply to all of them: (_a_) The chest register must never be carried above [Illustration: f-sharp']. (_b_) [Illustration: e' f'] should be "covered" or modified chest tones. (_c_) In all cases [Illustration: f-sharp''] must be a head tone. (_d_) In quick passages chest should not be carried beyond [Illustration: d-flat']--_i.e._, [Illustration: d' e' f'] are middle in quick passages. CHAPTER XI. FURTHER CONSIDERATION OF THE REGISTERS OF THE SINGING VOICE. It will, it is hoped, be apparent to the reader that the subject now under treatment may be considered either theoretically or practically. If science be exact, systematized, and, when complete, unified knowledge, then every source of information must be employed in the investigation of so difficult a subject as the registers. There may be differences of opinion as to the relative importance of some of these means of investigation--_e.g._, auto-laryngoscopy, but that it should be utilized, there can be no question. The value of photography of the larynx, as carried out up to the present, may be questioned; but there can be no doubt that if this method of studying the action of the vocal bands could be pushed to a certain point, much light might be thrown on the questions at issue.