Which preposition to use with poundage

as Occurrences 1%

The very feel of the man in the saddle was different, not so much in poundage as in a certain exquisite balance which he maintained but the pause lasted no longer than a second after the welcome daylight flashed on the eyes of Alcatraz.

of Occurrences 1%

As though there was a poundage of joy and additional muscle in self-mastery, the frame of the chestnut filled, his neck arched, and there came into his eyes that gleam which no man can describe and which for lack of words he calls the light of the wild.

Which preposition to use with  poundage