The "Blue Book", by Semper Idem (it is believed to be the pseudonym of Charles F. Heartman) was written in 1936 as an attempt to describe the Guide Books to the bordellos and prostitutes in New Orleans. This is a very rare book!! There were many "Blue Books" over the years, and this book is a compilation and explanation of most of these guide books published over the years during the heyday of legal prostitution in the infamous Storyville district of New Orleans. The original "Blue Books" advertised the beauty and quality of the bordellos and the women who worked there. Sex was never mentioned in the books, and neither was prostitution, but their message was clear. One of the early books carried the title of "Blue Book" at the top and "Tenderloin 400" at the bottom. 'Tenderloin' was one of the terms for districts known for prostitution. The '400' parodied a published list of important and influential Americans.

This book is rich with illustrations and facsimiles of original documents and pages from the "Blue Books" themselves. Some of the illustrations include:

License issued to a prostitute

Tax receipt for keeping a disorderly house

Tax receipt for exercising the Profession of lewd and abandoned woman

Society column of "The Mascot" announcing the publication of a Guide to houses of Prostitution

Pages from "The Lid" (one of the earliest 'Blue Books')

Pages from "Hell-O" (another early 'Blue Book")

Pages from "Sporting Guide"

Cover of the "Blue Book", 1895

"A Directory of the Tenderloin"

Pages of the "Blue Book", 1905

Cover of the "Blue Book", 1906

Cover of the last "Blue Book", 1915