In many old chemistry books there were limitations on how chemical structures could be represented driven, presumably, by the desire to use available typesetting methods to save costs.
For example, this is a page from a book on industrial chemicals published in the 1930s:
The distorted hexagons are 6-membered aromatic rings but are typeset from vertical and 45° lines with none of the double bonds explicitly shown.
When and how did chemical typesetting become more "realistic" with, for example, proper hexagons for aromatic rings and the correct description of double bonds where appropriate?