The Final Adventures of Sherlock Holmes Hardcover by Sir Arthur Conan Doyle (Author), Peter Haining (Introduction)
 
According to the generally accepted viewpoint the Complete Adventures of Sherlock Holmes consist of sixty cases-fifty-six short stories and four novel length tales. But, as this book will show and as more than one Sherlockian expert has already proclaimed, there are in fact twelve more Sherlock Holmes items which should rightly be included in the canon. What, in fact, Sir Arthur Conan Doyle left us of his immortal sleuth was seventy-two items which are all essential to a full understanding of the genius of Holmes. The reasons for these 12 items being omitted will be discussed here in detail, item by item. They are all being collected together in one volume for the very first time, and as such, form an essential addition to the existing definitive two-volume edition of the stories. The assembling of these rare and difficult-to-obtain items has naturally called for considerable detective worrk of its own- such has been their obscurity-and fellow Sherlockians in both Britain and America have assisted me so that we can at last make easily available the complete canon of Sherlock Holmes Adventures. -from the Introduction by Peter Haining
 
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