The microtomist's vade-mecum : a handbook of the methods of microscopic anatomy / by Arthur Bolles Lee.

Date:
1890
Catalogue details

Licence: Public Domain Mark

Credit: The microtomist's vade-mecum : a handbook of the methods of microscopic anatomy / by Arthur Bolles Lee. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    double-stain with gentian-violet and eosin; and mount in balsam or damar. That, or something like that, is now the practice of many of the most advanced workers; and I know of no method that seems to have equal claims to be considered a classical method of general morphological investigation. As regai'ds the method to be used for imbedding, I take it that the paraffin method is the method 2^ar excellence for small objects (objects up to 5 or 7 millimetres diameter); whilst the collodion or “ celloidin ” method is the method par excellence for large objects. As regards the rival claims of the method of staining objects in toto before section cutting, and that of staining the sections, I confess that I cannot see any reason for preferring the practice of staining in toto, which I consider only has a raison d’etre in the case of objects which are not to be cut into sections. As regards the rival claims of the practice of staining sections on the slide, and that of staining them in watch-glasses, I think that all small sections may be conveniently stained on the slide, and that all large ones should be stained in watch-glasses ; in other words, the watch-glass process is the proper process for celloidin sections, and the slide process is the most convenient one for paraflBn sections. 3. The treatment of objects which can be studied without being cut into sections is identical with that above described, with the omission of those passages that relate to imbedding processes. Its normal course may be described as fixation, washing out with alcohol, staining with alcoholic borax-carmine or some other alcoholic stain, treatment with successive alco- hols of gradually increasing strength, final dehydration with absolute alcohol, clearing, and mounting in balsam. This method, which may be termed the dehydration method, is generally preferred, as a general method, to what may be termed the wet methods, by which objects are prepared and preserved in aqueous media. The chief reason for this lies in the great superiority of the dehydration methods as I'egai’ds the preservation of tissues. The presence of water is the most important factor in the conditions that bring about the decomposition of organic matter, and its complete removal is the chief condition of peimianent preservation. It is of course not intended here to suggest that wet methods of prepara- tion should be altogether discarded. They have great value, they are even indispensable, for special ends; and all that is intended to be suggested is, that they should be regarded not as general but as Special methods. 4. In the preparation of entire objects or stnicturcs that