A treatise on the diseases of the nervous system : by William A. Hammond.

  • Hammond, William A. (William Alexander), 1828-1900.
Date:
1881
Catalogue details

Licence: Public Domain Mark

Credit: A treatise on the diseases of the nervous system : by William A. Hammond. Source: Wellcome Collection.

Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.

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    II^TEODUCTION. THE IMTBUMENTS AND APPARATUS EMPLOYED IN THE DIAGNOSIS AND TREATMENT OF DISEASES OF THE NERVOUS SYSTEM. Diseases of the nervovis system, like those of the heart, lungs, and larynx, require special means of investigation and treatment. In no department of medical science has progress been more decided during the last decade than in that class of aiFections considered in this trea- tise, and undoubtedly a great deal of the advancement is due to the instruments and apparatus by vi'hich scientific research in this direction has become practicable. In the present chapter I propose to describe the instruments and apparatus employed in the diagnosis and treatment of diseases of the nervous system, and to explain the methods by vphich they are used. THE OPHTHALMOSCOPE. The ophthalmoscope consists essentially of a concave mirror perfo- rated in the centre, and of a double-convex lens. Several modifications of this arrangement are in use, but the simplest instrument is, in my opinion, the best for ordinary use, and this is Liebreich's, though, when very great exactness is required, as, for instance, in determining the depth of an atrophic excavation of the optic disk, Dr. Loring's ophthal- moscope is far preferable to any other. Liebreich's oplithalmoscope consists of a polished steel mirror about one and three-quarters inch in diameter, concave, and perforated in the centre by a hole about the one-twelfth of an inch in diameter. The edges of this aperture are beveled, so as to afford as little obstacle as possible to the passage of the rays of light to the eye of the observer. The mirror is set into a bronze ring with a handle, and there is attaclicd also to this ring a clip for holding a concave ocular lens, 2