Born in Geelong, Victoria, Australia, James Morgan Walsh (1897 - 29 August 1952) moved to Britain early in his writing career, and published mostly mystery stories (often written as Stephen Maddock). He appeared in Hugo Gernsback's Wonder Stories in October 1931 with After 1,000,000 Years. This was a fairly trivial time travel story, although interestingly the heroine comes from the future, and is the builder of the time machine.
He is best known in SF circles for his second story, the space opera Vandals of the Void (Wonder Stories, Summer, 1931 and Hamilton, London, 1931, 288pp). A space fleet from Mercury threatens the other planets. There was a sequel The Struggle for Pallas in Wonder Stories, Fall 1931. He also wrote Vanguard to Neptune (Wonder Stories, Spring 1932)