Section 185H. In Boston, and in any other city or town which accepts the provisions of this section, the mayor or selectmen thereof may grant upon such terms and conditions as he or they may deem reasonable licenses for dancing schools, so called, to be conducted on week days only, and may fix the fee for said licenses within the limit hereinafter provided. He or they may revoke or suspend such licenses for just cause after hearing, due notice whereof shall have been given. The head of the police department in such city or town may cause such dancing schools to be inspected and supervised. Licenses granted as aforesaid shall specify the street or place and the number if there be any, or, if there is no number, then the location of the place, in which the license is to be exercised, and the license shall not be valid in any other place. Licenses so issued shall expire on April thirtieth of each year. The fee for such license shall not exceed five dollars. Whoever conducts a dancing school in such city or town unless authorized so to do by a license in full force and effect shall be punished by a fine of not more than one hundred dollars.