[1] Gammon declined a 1918 offer, made at the instigation of Scottish etcher Muirhead Bone,[2] of a place at the Slade School of Fine Art, but nonetheless had a successful career as a freelance illustrator and writer.
For 60 years he wrote and illustrated a feature column for the Cyclists Touring Club's Gazette.
The dropping of another column, "In the Open Air", for Scout magazine, resulted in international protests and it was restored.
Travelling by motorcycle, he would attend horseracing at Goodwood or motor racing at Brooklands, make sketches, and ride quickly back to London to deliver them.
[1] During World War II he moved his family to South Wales, and became a hill farmer, managing 40 acres (16 ha) in the Llanthony valley near Abergavenny.