I was first taught curly arrow pushing in 1968, and have myself taught it to many a generation of student since. But the other day, I learnt something new. Nick Greeves was kind enough to send me this link‡to the origin of curly arrow pushing in organic chemistry, where the following diagram is shown and Alan Dronsfield sent me two articles he co-wrote on the topic (T. M. Brown, A. T. Dronsfield and P. J. T Morris, Education in Chemistry, 2001, 38, 102-104, 107 and 2003, 40, 129-134);† thanks to both of them.