The proprietor of every moving-picture house must show on the screen at least once during each performance, and for at least one-half minute each time, a diagram of the seating arrangement of each floor, showing plainly the location of each exit. Every such diagram shall have the following statement printed underneath in letters sufficiently large that they may be easily read from any portion of the auditorium: “The laws of New Jersey require that this diagram be shown in all moving-picture houses at least once every performance and kept on the screen for at least one-half a minute. Penalty for nonobservance, one hundred dollars.”