Austin Hall
4 appearances across 4 restored issues — every one readable in full, free.
The Popular Magazine, March 7, 1922 — 1922 “From a Line of Kings” · p.48 Read the full issue (208 pages) → 
The Blue Book Magazine, October 1923 — 1923 “Rex Takes Them Out” · p.23 Read the full issue (212 pages) → 
Weird Tales, Vol. II, No. 2 — 1923 “The People of the Comet” (serial) · p.4 Read the full issue (98 pages) → 
The Blue Book Magazine, January 1924 — 1924 “Old Rex Retires” · p.76 Read the full issue (216 pages) → Appearances are extracted from each issue's own printed contents page; entries we can't read confidently are withheld rather than guessed.