the so-called head register of the female voice, as well as two small cartilages in the vocal cords.[14] [Footnote 11: _Proc. Royal Society of London_, vol. vii. No. 13, 1855.] [Footnote 12: _Zeitschrift der Ges. der Aerzte zu Wien_, April, 1858.] [Footnote 13: _Wien. Medicin. Wochenschrift_, March, 1858.] [Footnote 14: _Altes und Neues_, Leipzig, 1861.] HISTORY OF THE RHINOSCOPE.--Rhinoscopy, or the art of viewing the naso-pharyngeal space by placing a small mirror behind the velum palati, naturally suggested itself almost as soon as any attempts at laryngoscopy were made, but in the literature we find that Bozzini was the first to clearly express the idea.[15] [Footnote 15: _Loc. cit._] A number of years later Wilde endeavored to see the opening of the Eustachian tubes by means of a small mirror: an account of these experiments he published in his famous work on the diseases of the ear. In 1836, Baumès used the rhinoscope, and claimed to have seen ulcerations in the naso-pharyngeal cavity.[16] It remained, however, for modern times to develop this field of research, and it is again Czermak whom we have to thank for the perfection of this valuable means of diagnosis. [Footnote 16: _Loc. cit._] THE LARYNGOSCOPE.--The laryngoscope as it is used at the present day, both by the specialist and the general practitioner of medicine, consists of a so-called laryngeal mirror and of an illuminating apparatus more or less complicated. The laryngeal mirror is a small circular glass mirror mounted in a metal frame varying in size from ¾ inch to 1½ inches in diameter, and attached to a wire stem at an angle of 120°. This stem, about 4 inches in length and about 1/10 inch in thickness, should be soldered to the back of the mirror in such a manner that the rim of the frame forms the angle with the stem, and should not be below it, as this would increase the diameter of the instrument without increasing its reflecting surface. The stem is made to slide into a hollow handle of wood, ivory, or ebonite, and is clamped at any desired length by a set-screw. This arrangement is preferable to having the stem permanently fixed in the handle, inasmuch as the stem can be pushed entirely into it, thus economizing space and rendering the instrument more portable, and also allowing an adjustment of the length of the stem when in use. The handle should be 4 inches in length, and of the thickness of an ordinary lead-pencil (Fig. 1). [Illustration: FIG. 1. Laryngeal Mirror.] Mirrors of various shapes have been used, but it has been found that the circular form is the one most easily borne by the patient, and can be used in {22} a greater number of cases than any other shape, at the same time giving the largest reflecting surface for its size. However, in cases where an hypertrophy of the tonsils is present an oval mirror can be introduced between the protruding glands more easily than a round one.