Who murdered Grogan the poet?

Short Story (1,820 words)

A whodunnit set in rural Ireland. The elderly poet, Grogan, married to a young wife, has been murdered in a room over his his garage by gassing. But there is no gas laid on to the garage and the house is 100 yards away.

So who was the culprit? And how was the gas brought to the garage?

Evening Standard, Monday 2nd April 1956, p. 11.

Included in Crime and Detection, ed. John Higgins.