According to the Internet source given below, Ivor [Jack] Ayre was a Canadian pianist and a member of the Dumbells, which entertained Canadian troops during the First World War. He continued to perform with the Dumbells when they reformed as a civilian touring group performing songs, skits and musicals across Canada, the United States and the United Kingdom.
A one-off composer, his The Dumbell Rag (1920). was said to have sold more than ten thousand copies.

Websites:
	Jack Ayre	Biography by wikipedia.org.