Willam Sherpes is the pseudonym of an Italian author, to me unknown, unfortunately. This book praises spiritualism but has lot of data about italian cases, and photographs quite rare and unusual.
Exists another version with a blue binding (mine is red), I don't know it is's the first or the second one. My copy has a tipped-in page at page 226 about rabdomancy, and various pen corrections in the text.
The market stall from which I bought the book (on the Navigli, in Milan), had also the other copy, but I decided on this one because of the tipped-in sheet and the corrections.
The current value is the price at an antiquarian library in Dec. 2002.