“The Adventures of Sherlock Holmes” by Arthur Conan Doyle — a free Project Gutenberg ebook, available to read as an EPUB on BookMarket.
Subjects: Detective and mystery stories, English; Holmes, Sherlock (Fictitious character) -- Fiction; Private investigators -- England -- Fiction. Original source: https://www.gutenberg.org/ebooks/1661.
This ebook is in the public domain in the United States; the Project Gutenberg eBook license applies to the original text.