Two or more counties may join in building or purchasing an almshouse in common, at a place agreed upon by the boards of chosen freeholders of the counties, and which when built or purchased, shall be under the joint direction, superintendence and government of such boards, which boards may:

a. Appoint such officers, committees or boards, and employ such persons, as they shall deem necessary for the management and maintenance thereof; and

b. Make such rules, regulations and by-laws respecting the almshouse as they shall from time to time deem proper.