This is sad news.
I bought a 78rpm single of his on the Pye label back in the late fifties (unbreakable plastic - an experiment that was made redundant by 45rpm vinyl.) Anyway, this was his version of "The Talking Atomic Blues" (credited to Partlow) aka "OLd Man Atom" and
"To Be Or Not To Be". A classic song and performance.
Years later I bought his excellent LP "Songs of Trouble and Celebration" which included the marvellous "Take The Children And Run"
(by one Don Lange) - a chilling prophesy of nuclear plant disaster, written long before Chernobyl.
As Elijah Wald says (above) :- "never a star, never a name that could attract huge crowds"   but someone who certainly deserved a full obituary.