"I come hard, in the mornin' light
My mother says "Girl you sure live your life right."
Oh momma dear, we're the fortunate ones
And girls, they wanna be tied to a bench and forced to have fun"
John Lange, the author writing under the name John Norman, was a professor of psychology at Queen's College (NYC, USA). Diagrams (and photos) of slave positions (such as nadu, bara, sula, tower, and whip) can easily be found online.
Personally, I prefer William Moulton Marston. He was another psych professor (at American and Tufts) and a polygamist who with his wives (attorney Elizabeth Holloway and editor of 'Ladies Home Journal' Olive Byrne) wrote 'Wonder Woman' which has a whole lot of D-s undertones. (Bill's third wife Marjorie Huntley ran the business end of things.)
Fun Fact: Olive was raised by her aunt Margret Sanger because her mother Ethel was living in France to avoid prison in the USA -- having been convicted of "obsenity" for distributing contraceptives in New York State.