A laboratory guide for histology : laboratory outlines for the study of histology and microscopic anatomy / by Irving Hardesty ... With a chapter on laboratory drawing by Adelebert Watts Lee ... With 30 illustrations 2 of which are in colors.

  • Hardesty, Irving, 1866-
Date:
1908
Catalogue details

Licence: Public Domain Mark

Credit: A laboratory guide for histology : laboratory outlines for the study of histology and microscopic anatomy / by Irving Hardesty ... With a chapter on laboratory drawing by Adelebert Watts Lee ... With 30 illustrations 2 of which are in colors. 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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    charged, is now to be used on the drawing exactly as a pencil. If the ground color shows streaks, it may be converted into a uniform mass by rubbing over it with an uncharged tortillion. It will be found that the tortillion's point, after some use, has become worn off and quite flexible, an occurrence which rules out its further employment in the fine work. For drawings of small area and requiring a light shade of the ground color, the necessary graphite may be made available by simply rubbing the point of the HB pencil, flat-wise, over an area of an extra piece of drawing board until the surface is densely black (thus obviating the need of a file) and applying the tortillion to this surface. 3. With a brush and fluid pigment the best ground color can be laid. The brush, however, is such a stranger in the hands of most, that the beginner sel- dom accomplishes good work with it. Practice will, nevertheless, enable one Fig. 10.—Illustrating the method of preparing fluid pigments from the solid block. to pursue the method with increasingly better results, and because of its greater possibilities, its use is strongly recommended. As pigment, either a solid or fluid variety may be employed, and of these Winsor & Newton's Ivory Black and Process Black may serve as respective examples. A solution of Ivory Black, from the solid cake, is prepared as follows, illustrated by Fig. 10: The color-block, a, is firmly held between the thumb and first two fingers and then rubbed vigorously in a few drops of water placed in one of the com- partments of the mixing-dish h. Gradually the water will take up the color until it assumes a deep black tone. Then the trituration of the color should be stopped and clear water added to the fluid in the mixing-dish until it is about twice as dark as the tint desired for the ground color. The brush is charged with this fluid simply by immersing it in the same and allowing it to draw as much of the pigmented water as it will. Here the beginner is apt to make a mistake by freeing the brush of some of its charge until its point is finely tapered.