In 1913, after a few months of university, Arlen moved to London to live by his pen.

And I must do that by my pen.

He supported himself by his pen, and he became a political pamphleteer.

He went to London to seek a livelihood by his pen.

He just got spooked when I walked by his pen.

While at Cambridge he earned his living by his pen.

Towards the end of his life he was reduced to great poverty, and lived by his pen.

Otherwise he lived by his pen, and often fell short of money.

He now supported himself by his pen, and became a regular contributor to the reviews.

Some were, of course, ephemeral, including books and articles written in the 1930s when he lived by his pen.