Which preposition to use with schenck

of Occurrences 2%

I admired the very presumption of the theory, and finally told him to call the next day on my agent, Mr. Schenck, at such a number (Martin Baum's) in Maine Street, to whom, in the mean time, I transferred the hoax, and duly informing Schenck of the affair; and I do not recollect, at this time, how he shuffled him off.

from Occurrences 1%

"Are ye men?" exclaims the deep voice of Mr. MELANCTHON SCHENCK from behind the lantern, "and would ye madly incur death before having taken out life-policies in the Boreal?"

Which preposition to use with  schenck