It seems to me either that you have not read the full account of the case, or else you do not appreciate the work of the detective. Why, all the clue he had was a button.
Being one of the first works of its genre, and provided the time it was written, I found it most entertaining. The resources taken by the author fit accordingly. It is not his fault that they were so much abused by his successors.
Some stories are written with characters that you just want to dislike, but is it true that they are bad? I just couldn't tell in this book with one of the main characters of this book until at the end of the book. I really liked this book!