THE DRAWING OF MICROSCOPIC DETAILS.
Questions relating to the drawing of microscope sections may now be dealt with. Usually these are drawn in pencil and reproduced by means of lithography; this is quite wrong, for in addition to its being an unnecessary expense, it is also an inconvenience to a reader, since the figures are necessarily divorced from the letterpress. There are very few histological details which cannot be represented by line blocks, and with a proper co-operation between the author, the block maker, the printer and the publisher, even the delicacies of karyokinesis could be reproduced in the text.
For demonstration purposes, transverse sections of plant-structures may first be taken.
The walls of the various elements may be represented by lines of more or less equal breadth, but in those cases where the walls are particularly thick, e.g., the elements of the wood, the thickening may be represented by an additional line. This is seen in Fig. 27, in which it will be noticed that the middle lamellæ of the wood-elements are represented by black lines.
