Tharkol, Lord of the Unknown
| First published | 1950 |
|---|---|
| Publisher | World Distributors / Sydney Pemberton |
| Format | Paperback |
| Type | Novel |
| Cover art | H. W. Wesso |
| Pages | 160 |
| Price | 1/6 |
Reprint of ''The Prisoner of Mars'', a Hamilton serial which appeared in ''Startling Stories'' in May 1939.
First book edition.
According to http://www.geocities.com/Area51/Cavern/5792/harbottle.htm, the cover art was copied from a Hans Wesso illustration in the May 1939 issue of "Startling Stories".