If you want the actual bylaw:
7. Music, sound, advertising and similar activities
Except with written permission from the Operator, no person on the railway shall, to the annoyance of any person:
(i) sing; or
(ii) use any instrument, article or equipment for the production or reproduction of sound.
(2) Except with written permission from the Operator, no person on the railway shall:
(i) display anything for the purpose of advertising or publicity, or distribute anything;
(ii) sell anything or expose or offer anything for sale; or
(iii) tout for or solicit money, reward, custom or employment of any kind.
(3) A person shall have the written permission referred to in Byelaws 7(1) or 7(2) with him when undertaking the activities referred to in Byelaw 7(1) or 7(2) and shall hand it over for inspection when asked by an authorised person. A person shall comply with any conditions set out in or attached to the written permission.