Transportation by motorbus, although of recent origin, has advanced rapidly in its development but is still undergoing a process of evolution. Less than 10 years ago, motor carriers were mostly “jitneys” and were heartily disliked by electric-railway officials. Now, motorbuses are developing a field of their own and are rendering a service not supplied by any other transportation agency, two of their most valuable functions being the building up of new territory and acting as feeders to established lines in the more thickly settled areas. The first steps in their development took place while engaged in local service, but the trend toward interurban business soon became manifest.
In California, within the last 10 years, the interurban business has increased from that of a few isolated individuals to the operating of approximately 1000 vehicles, which cover the entire State and, in 1923, carried about 25,000,000 passengers. The service rendered by automobile stages is divided into three distinct classes: (a) local city-service, (b) local intercity-service and (c) through-intercity service. Many manufacturers have endeavored to build what they call “stage chassis,” having in mind their possible adaptability to freight service. But the requirements of passenger service differ greatly from those of freight service and a special type of chassis is necessary. These requirements are described in detail.
Many parts of the equipment should be improved. The braking systems at present in use are said to be entirely inadequate. Data are given concerning the wear of both the emergency-brake and the foot-brake linings. Wooden wheels have been unsuccessful, but when cast wheels are used the wheels should be cast without the hub and the hubs fitted to them. Troubles due to the use of dual rear-wheels are being overcome.
In the opinion of the author, sufficient study has not been given to the tire problem. The products of different tire manufacturers do not match. Different makes of tire should be made interchangeable and the same size of tire should be used for the whole fleet. To get the longest life from a tube, the suggestion is made that a size should be selected that will just fill the casing before sufficient air is put into the tube to stretch the rubber. In such a tube the tread will not stretch “paper thin” and will not be easily punctured.
In the stage and motorbus business the heaviest expenses are those due to (a) obsolescence of bodies, to keep abreast of the times; (b) the reconstruction of stock chassis, to make them conform to stage needs; and (c) maintenance. Reconstruction of bodies is necessary because new cars must be modified to meet local conditions. One modification usually involves another. On rebuilt cars the annual maintenance cost amounts to more than 60 per cent of the cost of the new equipment.
The statement is made that if manufacturers do not pay more special attention to stage equipment and prepare themselves to fill buyers' specifications, general assembling plants will spring up, or stage companies will be forced to expand their present plants to complete the assembling.


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