Handbook of bacteriological diagnosis for practitioners : including instructions for the clinical examination of the blood / by W. d'Este Emery.

  • Emery, Walter d'Este, 1870-1923.
Date:
1902
Catalogue details

Licence: In copyright

Credit: Handbook of bacteriological diagnosis for practitioners : including instructions for the clinical examination of the blood / by W. d'Este Emery. Source: Wellcome Collection.

Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.

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    with some firm substance and not merely embedded therein. Two embedding materials are in general use—paraffin and celloidin. ' The latter will not be described, as it is only necessary for special work and for ordinary purposes cannot compare with paraffin for beauty of results and faciHty of application. In the paraffin process the tissue is infiltrated through- out with hard paraffin (such as is used for the better varieties of paraffin candles) so that every cell and every fibre is permeated and supported on every side. To do this requires a number of processes. It would be of no use to immerse the block of tissue in the paraffin just as It is, for the paraffin would not wet it, much less soak into it. The water is first removed ; and this is done by soaking the material in absolute alcohol. But alcohol does not dissolve or mix with paraffin; it is therefore necessary to remove it by means of some fluid which will mix with it on the one hand and paraffin on the other. Of these there are many ; xylol, chloroform, benzine, cedar oil, and many more are in use for special purposes. Chloroform answers most purposes and is to be generally recommended. The block of tissue is now ready to be soaked in melted paraffin ; it is kept in a bath of this substance until the chloroform has been entirely driven off and replaced by the paraffin. The whole is then allowed to cool, is shaped into suitable blocks, and is then ready for cutting. We shall now describe the processes in fuller detail. FIXING MATERIAL FOR CUTTING. These processes must be understood by all practi- tioners, even although they do not intend to cut sections