Section 71. Articles deposited in pawn with a licensed pawnbroker shall, unless redeemed, be retained by him on the premises occupied by him for his business for at least four months after the date of deposit, if not of a perishable nature; and, if perishable, for at least one month after said date. After the expiration of the applicable period of time, he may sell the articles by public auction, apply the proceeds thereof in satisfaction of the debt or demand and the expense of the notice and sale, and pay any surplus to the person entitled thereto on demand; provided, that no such sale of any article which is not of a perishable nature shall be made unless not less than ten days prior to the sale a written notice of the intended sale shall have been sent by registered mail to the person entitled to the payment of any surplus as aforesaid, addressed to his residence, as appearing in the records of such pawnbroker. No article taken in pawn by such pawnbroker exceeding twenty-five dollars in value shall be disposed of otherwise than as above provided, any agreement or contract between the parties thereto to the contrary notwithstanding. Articles of personal apparel shall not be deemed to be of a perishable nature within the meaning of this section.