General considerations that affect the attainment of adequate lighting are mentioned, it being stated that proper lighting of the interior of a motorbus is influenced by limitations peculiar to the service, such as vibration, scant headroom, a restricted energy supply and relatively large voltage-variations. Available types of bus-lighting equipment are analyzed as to their suitability, from six different standpoints that are stated. “Glare” is defined and means of obviating it are suggested, inclusive of a discussion of desirable types of finish for the interior with regard to reflecting surfaces.
The severe vibration produced by many motorbuses demands head-lamps of more rugged construction than that used for the headlighting of private cars. Eight essentials for motorbus head-lamps are specified. A very large percentage of the glare and poor illumination of the motor vehicles on the roads results from improper adjustment or the lack of any means for adjustment of the head-lamps.
Tail-lamps, stop and direction signals, step-lamps, trouble-lamps, lights for the signs and marker-lights are discussed. Standard incandescent lamps are recommended for use. The most suitable type of electrical system for motorbus service is outlined briefly, consideration being given to the wiring needed to minimize voltage-drop, switches, lamp sockets, fuses, generator and voltage regulator.