For the purpose of extending cooperative agricultural extension work provided for by the act of congress, entitled “An act to provide for cooperative agricultural extension work between agricultural colleges in the several states receiving the benefits of an act of congress approved July 2, 1862, and all acts supplemental thereto, and the United States department of agriculture,” approved May 8, 1914, in any county employing a county agent under the terms of said acts, the board of county commissioners is authorized, upon petition of at least one hundred bona fide taxpayers within the county, to provide and appropriate such funds as are necessary for maintenance of cooperative extension work in agriculture and home economics within the county.