Organic molecules perspective drawings

Finally, in the drawing of three-dimensional representations of organic molecules (e.g., Figures 3.1f,g, 3.2c,d, 3.5d, 3.7,3.8, and 3.10a,c), attempts are made to provide some perspective to the pictures. Frequently, shading, making some lines heavier than others, and so on, is employed. This is done both to reinforce the spatial relationships to which you must become accustomed and to acquaint you with processes about which you must learn. 

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