And every stipend which shall be augmented after the passing of this Act shall be wholly modified in grain or victual, even although part of the whole thereof shall have been previously modified in money, or although part of the whole of the teinds shall be money teind, unless where it shall appear necessary, on account of the state of the teinds, or on account of the interest of the benefice, or on account of the nature of the articles other than grain or victual which have been in use to be delivered in kind as stipend, that a part of the said stipend should be modified not in grain or victual but in money, or should be modified in such other articles as have been in use to be delivered in kind as stipend.