Jackson Gregory
3 appearances across 3 restored issues — every one readable in full, free.
Adventure Magazine, August 1916 — 1916 “Yahoya” · p.3 Read the full issue (228 pages) → 
Adventure Magazine Cover — 1918 “The Bells of San Juan” (serial) · p.38 Read the full issue (196 pages) → 
All Story Magazine, March 3, 1917 — March 3, 1917 “The Fire Flower” (novelette) Read the full issue (192 pages) → Appearances are extracted from each issue's own printed contents page; entries we can't read confidently are withheld rather than guessed.