When representing a solid object, such as a plant or an animal, to shew the external morphology, it is to be borne in mind that form is the main thing to represent, and this can be expressed by outline drawing alone. In fact, more or less primitive methods must be employed, and better models cannot be followed than the best wood cuts.
[Illustration: Fig. 9. The Lesser Celandine (_Ranunculus Ficaria_). By R. G. Hatton. (From Hatton's _Craftsman's Handbook_).]
[Illustration: Fig. 10. The Lesser Celandine. After Fuchs. (From Hatton's _Craftsman's Handbook_.)]
An examination of figures 10 and 12 will shew that Fuchs[A] attained his object by simple outline drawings; he never employed local colour, and shading he used very sparsely indeed, and then only to give expression to the form of some thick part. Fuchs's celandine (Fig. 10) should be compared with the drawing of the same plant (Fig. 9) by R. G. Hatton.
[Footnote A: The methods followed by the illustrators of the Herbals may be conveniently studied in Hatton's "The Craftsman's Plant Book," London, 1909, and Arber's "Herbals," Cambridge, 1912.]
[Illustration: Fig. 11. The Apple (_Pyrus Malus_). After Matthiolus. (From Hatton's _Craftsman's Handbook_).]
The methods of Matthiolus (Figs. 11 and 13) were somewhat more advanced, for he used shading not only to express form but also to give a certain amount of relief. It will be noticed that he shaded by lines which followed the moulding of the parts.
The work of Riocreux (Fig. 8) should also be studied; it will be observed that he managed to get a very high relief in his drawings by the simple means of straight or curved lines, according to the shape of the part, of varying thicknesses.
[Illustration: Fig. 12. Charlock (_Brassica Sinapis_). After Fuchs. (From Hatton's _Craftsman's Handbook_)]
There is no necessity for keeping all the lines of even thickness. For instance, provided the character of the form is not altered, the outline on the shaded side may be made thicker than on the illuminated side; also distance can be indicated by the use of thinner lines, for these, although really black, will give the impression of greyness. Then again, a line may be drawn with local increases and decreases in thickness, as in ordinary writing, and such lines drawn by a skilled hand can be made to express a marvellous amount of modelling.