This paperback series was published first in 1892. Initially there were 38 books. The title list was expanded such that by 1901 there were 425 books in the series list. Determining the date of publication can be done by looking at the Lupton address. Note that the date on the book is the original publication date. The Lupton address can indicate a later date of publication for the particular book. This series with a change in format was continued by the Federal Book Company. (See here)

(52 Duane Street address)-1899-1902