The human brain : histological and coarse methods of research : a manual for students and asylum medical officers / by W. Bevan Lewis.
- Lewis, William Bevan, 1847-1929.
- Date:
- 1882
Licence: Public Domain Mark
Credit: The human brain : histological and coarse methods of research : a manual for students and asylum medical officers / by W. Bevan Lewis. Source: Wellcome Collection.
Provider: This material has been provided by King’s College London. The original may be consulted at King’s College London.
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![sulci, and this with care, as tubercle along the course of the vessels is found with far greater difficulty here than at the base or up the Sylvian fissure. Next strip off a large portion of arachnoid and pia mater from the surface, and transfer it to a deep vessel containing water, the arachnoid surface being uppermost. Observe the velvety aspect of the lower surface, due to a fine pile of blood- vessels, and the very rich fringe of vessels along the inter- gyral folds, for the supply of the cortex deep within the sulci. Seize with a forceps one of these richly fringed folds and snip off a portion with a scissors, floating it on to a glass slide, with its vessels disentangled and spread out. Eemove also to another glass slide a portion of the membranes de- tached from the summit of a convolution, and study them by means of a hand-lens, both in reflected and transmitted light. Edu-cate the eye in this manner to the recognition of the various healthy and morbid structures to be found here. For microscopic purposes, both these slides last mentioned should be reserved, whilst a small portion of brain covered by its membrane, and including two adjacent convolutions, should also be set aside. These will afford subjects for a hircCs-eye xieio of the surface under low powers of the micro- scope, such an examination being always insisted upon as especially valuable. The portion of brain must then be frozen and cut in such a direction that the sections so obtained represent both gyri with the intervening sulcus bridged over by arachnoid. We thus obtain very beautiful slides for fresh examination, which afford us the opportunity of minute examination of the cortex and the connections and relation- ships between it and its membranes. The large superficial veins at the vertex where they 0]3en into the longitudinal sinus, are occasionally found plugged by thrombi; they should therefore always be examined with the object of ascertaining the nature of their contents, esj)e- cially if there is evidence of inflammation of the dura mater or its sinuses, or of purulent meningitis. The student should also take every opportunity of follow-](https://iiif.wellcomecollection.org/image/b21292966_0041.jp2/full/800%2C/0/default.jpg)
