The proviso to the fourth section of an act, entitled “An act for the better protection of the wages of mechanics, miners, laborers and others,” approved the ninth day of April, 1872,¹ shall not hereafter be so construed as to in any manner apply to coal lease mortgage or mortgages, or to make the same a lien preferred to the lien of the wages of labor mentioned in said act, but that such claim of wages shall be a lien preferred thereto.