After the ratification of this Constitution there shall be paid out of the treasury of this state at the time and in the manner provided by law, the sum of not less than thirty-six thousand dollars per annum as interest on the funds of the University of Alabama, heretofore covered into the treasury, for the maintenance and support of said institution; provided, that the legislature shall have the power at any time they deem proper for the best interest of said university to abolish the military system at said institution or reduce the said system to a department of instruction, and that such action on the part of the legislature shall not cause any diminution of the amount of the annual interest payable out of the treasury for the support and maintenance of said university.