JF Ptak Science Books Quick Post
The author of this pamphlet (written and probably published in 1939) was described in at age 95 in 1995 as "America's oldest living revolutionary". He did write a very concise catechism on Marxism, though it wasn't actually a literal A-B-C of the subject, though it did deal with the basics of the philosophy. It does seem from arm's length that Cowl led an interesting and very full life (https://pubs.socialistreviewindex.org.uk/sr208/obit.htm).
"HE IS America's oldest living revolutionary. Carl Cowl, aged 95, not only remains a committed Marxist; by a curious process of osmosis he now looks a dead ringer for his famous mentor. When he visited Marx's tomb in Highgate Cemetery in London last week, one young schoolgirl even asked him if he and Marx were one and the same person. "I told her no, I wasn't, that Marx was a good deal more important than I have ever been." Secretly, you suspect, he is flattered at being mistaken for the Great Bearded One...Almost 80 years since he first became a socialist, Cowl's faith in socialism's future remains as strong as ever."--Independent,.https://www.independent.co.uk/news/uk/home-news/marxism-never-died-for-carl-95-1590586.html