Any person who shall, after his scales, weights and measures have been inspected in accordance with the provisions of the fifth section of this act, alter or cause to be altered his said inspected scales, weights and measures so that they be decreased in size or amount, or who shall substitute for said inspected weights and measures any other weights and measures of smaller size or amount, shall, upon arrest and conviction before a magistrate or justice of the peace, be fined not more than twenty dollars and cost of court, and in default of the payment of such fine and costs shall be imprisoned for a period of not more than ten days.
73 P.S. § 1757