The problem is, in the 18th, 19th and early 20th centuries masturbation was considered to be horrible and devastative "self-abuse", leading to countless and severe physical and mental ailments. It was scientific, medical and social consensus at the time. In fact, it was seen almost exactly as "child sexual abuse" nowadays, with the only difference that a masturbating child was himself (or herself - girls masturbate, too) abuser and abused, both in the same time. No adult was needed.
Anyway, enough of this diversion - let's get back to the main topic!