Why Do They Say Negatory?

This last example is particularly interesting because the author frequently uses the word negative in the same discussion and seems to introduce the term negatory to indicate a shade of difference, as if negative meant "negative" in the modern sense, while negatory meant something like "negating."

What does Negatory mean?

: marked by or having the nature of negation : negative negatory criticism.

Does Negatory mean negative?

marked by negation; denying; negative.