The president and trustees of any institution of learning established in the State of Louisiana, which is or may be hereafter incorporated as a body politic, in conformity with the constitution and laws of this State, who may wish so to do, can deposit in the treasury of the State of Louisiana all sums of money intended solely for the uses and purposes of such institutions of learning; and all sums so deposited shall be invested in the bonds or obligations of the State of Louisiana or of the United States, and the interest accruing thereon, as realized, shall be paid over to such corporation or again invested as they may desire.