Lyubavichi census #russia

Eli Eliach

I am looking to gain access to censuses taken in Lyubavichi (Russia), to search fore information on the Meris/Merris family.
I know of a census conducted there in 1850/1.
In the book "Igrot Kodesh" from the "Tzemach Tzedek" of Lubavich, the editors brought some data from this census.

Appreciate any help.

Eli Eliach
Modi'in, Israel