It is the true intent and meaning of the provisions of the act of assembly, entitled “An act for the better protection of the wages of mechanics, miners, laborers and others,” passed the ninth day of April, 1872,¹ that the several classes of laborers in said act mentioned shall have a preference over landlords, in all claims for rent of any mines, manufactories or other real estate, held under lease, where the lessee or lessees are the parties employing the miners, mechanics, laborers or clerks: Provided, That any person or persons claiming a preference as above provided, shall give notice of the nature and amount of his claim to the landlord or his bailiff, before the actual sale of the property levied upon.