A treatise on the diseases of the nervous system / by William A. Hammond; with the collaboration of Graeme M. Hammond.

  • William Alexander Hammond
Date:
[1891], ©1891
Catalogue details

Licence: Public Domain Mark

Credit: A treatise on the diseases of the nervous system / by William A. Hammond; with the collaboration of Graeme M. 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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    INTRODUCTION. THE IXSTRIMEXTS AXD APPARATUS EMPLOYED IX THE DIAGNOSIS AND THE ATM EXT OF DISEASES OF THE NERVOUS SYSTEM. Diseases of the nervous 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 dur- ing the last decade than in that class of affections considered in this treatise, and undoubtedly a great deal of the advancement is due to the instruments and apparatus by which 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 which they are used. Till: OPHTHALMOSCOPE. The ophthalmoscope consists essential]} of a oonoave mirror per- forated in the centre, and of a double-convex lens. Several modifi- cations of this arrangement are in ase, bul the simplest instrument is, in my Opinion, the besl for ordinary use, and this is Liehreielfs ; though, when very great exactness i> required, as, for instance, in determining tin- depth of an atrophic excavation of the optic disk. Dr. Loring's ophthalmoscope is tar preferable t<» any other. Liebreioh's ophthalmoscope consists of a polished steel mirror aboul one and three-quarters inch in diameter, concave, ami perforated in the centre by a hole ahoiit tin e-t\velt'th of an inch in diameter. The edges of this aperture are beveled, so a- to afford as little ob- stacle as possible to the passage of the rays of light to the e\. of the observer. The mirror is set into a hron/.e ring with a handle, ami there is attached also to this ring a clip for holding a concave ocular lens, which in some conditions of refraction, either in the eye of the \<-.i- :*