Exciting find tip-sleuths! Look what was hiding beneath the spine of my recently-aquired 1914 French Progressive Reader. A tome called The Crime Doctor. There is nothing in the rest of the book that gives away it's earlier life, just the printing on the spine - perhaps there is a WWI vintage recycling trend here?
The Crime Doctor was a book written by English author E. W. Hornung (of Raffles fame) in 1914 - the same year my edition of the French Progressive Reader was published. This version is Australian, and you can access and read the original online for free at The Internet Archive.
Any information about this would be most fascinating - drop me a message with your finds, tip-sleuths!