How to Work with the Microscope, Lectures. [With]

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1857 edition. Excerpt: ...be carefully washed, by agitating it in water, or by directing a stream of water upon it, from the wash-bottle (page 71). This washing is absolutely necessary to remove from the surface of the section particles of debris, which would render the appearances indistinct, and interfere with the clearness of the specimen when it was subjected to examination in the microscope. Drying the Tissue before Cutting the Section.--There are, however, many tissues, of which sections cannot be obtained in this simple manner, --thus it is almost impossible to cut sections of soft membranous textures perpendicular to the surface, sufficiently thin for examination. In such cases, it is advisable to pin the texture out upon a board when perfectly fresh, and expose it to the atmosphere until quite dry. Thin sections may then be cut very easily, and upon being moistened with water will resume their recent appearance. Hardening the Tissue.--Other textures, again, require special treatment in order to render them sufficiently hard to enable us to cut thin sections. Some require boiling for this purpose, others soaking in alcohol, or chromic acid, or in syrup, while not a few require special modes of treatment, which are applicable to them alone. Horn.--Thin sections of horn and textures of this description may be cut with a sharp strong knife. Hair.--There are many ways of obtaining thin sections of hair. Thus a number of hairs, may be united together by a little gum, so as to form when dry, a firm hard mass. Thin sections of this can readily be made, with a sharp knife, and the individual pieces may be separated from each other, by the application of a drop of water. These may be mounted in fluid, or dried and preserved in Canada balsam. Or the hairs may be..