Which preposition to use with magnifier

of Occurrences 2%

gen. is a great magnifier of honest mirth, by which (saith he)

with Occurrences 2%

The most exquisite work of literary art exhibits a certain crudeness and coarseness, when we turn to it from Nature,as the smallest cambric needle appears rough and jagged, when compared through the magnifier with the tapering fineness of the insect's sting.

from Occurrences 1%

" As he spoke, he bent over, and, taking a magnifier from his pocket, examined the lace, which still fluttered where it was caught.

Which preposition to use with  magnifier