by Major-General W H Sleeman, KCB.
The kind of thing the Web - and Project Gutenberg - was made for. All 77 chapters of it, written 1835-36 by the man who suppressed the Thugs. He may have knocked Thuggee on the head, but the tradition of the poisoners lives on - I must say I had no idea Sobhraj was out.
It'd take some time to read the whole thing. A chapter or two at a sitting seems more appropriate.