This series of paperback novels was introduced in January of 1893. There were 152 novels issued in this series. The original date of publication is listed on the front cover but the actual date of publication can be approximated by looking at the Lupton address at the bottom and seeing when Lupton was at that address (addresses and dates are shown here). 61 books were published in the earlier format.

The post-1902 books (#62-152) have the later format.