^The term "science fiction" would not be coined until 1929, but there were other terms used: "scientific romance" and "scientific fiction", for example.
^A pulp magazine was usually 10 x 7 inches, but magazines are often regarded as pulps even if they printed most or all of their run in other sizes – 11.75 x 8 inches is known as large pulp, and sometimes as bedsheet, though this latter term is confusing because "bedsheet" format can also refer to a different, significantly larger, magazine format.
^The Thrill Book was initially released in dime-novel format, but switched to pulp with its ninth issue. The typical dime-novel format was saddle-stapled, and either 5 x 7 inches or 8.5 x 11 inches; The Thrill Book was 8 x 10.75 inches.
^The term "different" for this sort of story had been coined by Robert A. Davis, one of the editors at Munsey.
^Palmer claimed the highest circulation of any science fiction magazine, but del Rey comments that though this may have been true, "Palmer's tendency to magnify everything about the magazine cannot be discounted."