At the first meeting of the board of trustees, the nine names who are not ex officio members, shall by themselves and by lot be divided into three classes, of three each, numbered one, two and three; the appointment hereby made of class number one shall terminate on the first Monday of October, 1856, number two on the first Monday of October, 1857, and number three on the first Monday of October, 1858; and upon the termination of the office of such directors, to-wit: on the first Monday of October in every year, an election shall be held at the institution to supply their place, and such election shall be determined by the votes of the members of the executive committee of the Pennsylvania state agricultural society, and the votes of three representatives duly chosen by each county agricultural society in this commonwealth, which shall have been organized at least three months preceding the time of election, and it shall be the duty of the said board of trustees to appoint two of their number as judges to hold the said election, to receive and count the votes, and return the same to the board of trustees, with their certificate of the number of votes cast, and for whom, whereupon the said board shall determine who have received the highest number of votes, and who are thereby elected.