RUBBER TIRES.
In a general way the automobile industry is divided into four branches: Manufacture of complete vehicles, manufacture of component parts, manufacture of accessories and manufac ture of carriage work and vehicle bodies. The last-mentioned branch has been taken over to a considerable extent by the concerns which built vehicles or carriages before the advent of the automobile. The division lines are vague. Many firms whose main product is motor cars make also motor wagons and motor trucks. A considerable number make only commercial motor vehicles and constitute what is often looked upon as a separate motor truck industry and have associations and trade journals apart from the rest. But the Society of Automobile Engineers, which is widely recognized as hav iing the common technical interests of the in dustry in charge, draws its membership from all branches and is extending its activities to matters related to the technics and production of motor boats, aeroplanes, tractors and self propelled farm machines. Its most important work has consisted in the establishment of standards in construction elements, being the selection of a limited variety of dimensions and shapes in raw materials as indispensable to meet the needs of the designers in the automo bile industry and, coupled herewith, uniting the producers of the materials in an understanding with the designers to the effect that minimum delay and lowest cost.are secured on both sides by avoiding departures from the selections made, these being subject to revision, however, from year to year. The value of this °standard ization° work for expediting and cheapening production, without interfering greatly with the freedom in new design or the advancement of merits in construction, has been recognized also outside of the United States.
Several large concerns manufacture within their own establishments and from raw mate rials the frames, axles, gears, clutches, shafts, springs, wheels, carriage bodies, as well as en gines and carburetors which enter into their completed vehicles, but a much larger number furnish the desired designs to manufacturers of component parts, especially the frames, axles, springs and wheels, and have them made to their order, sometimes under supervision by their inspectors. Many other automobile manu facturers adopt their design to a comprehensive selection of the components which the manu facturers of the latter have designed and pro duced for the market in general and with a view to the needs which, in their opinion, the builders of automobiles have in common.
About 50 firms make a specialty of producing engines for the industry. Large manufacturers of complete automobiles have been started on the plan of obtaining all but a few characteristic parts and features from the auxiliary branches of the industry and, in the measure as commer cial success was attained, have enlarged the scope of their individual design and production, finally controlling them in all the essentials.
The manufacturers of components, on the other hand, were usually engaged in forms of metal or steel manufacture having nothing to do with automobiles before they entered this field and, while many of them still continue such unrelated manufacture in other lines, the largest and most successful ones among them have as a rule confined themselves more and more to automobile products and turn these out in ever-increasing quantity. An exception in this respect is the manufacture of electric generators, motors and storage batteries, which remains almost a separate industry with its most important interests in other directions.
From the beginning the American automobile industry adopted the plan of making and selling complete vehicles to the public, while European manufacturers produced only a chassis and left it to the customer to have a carriage body fitted to it by a carriage builder of the cus tomer's own choosing. The American plan was later extended to embrace also the equip ment with accessories, such as lamps, odom eters, cyclometers, horns or other signal devices, windshield, shock absorbers, storage battery. Finally, an engine-starter equipment is now frequently also included in the outfit to which the selling price applies, and in some instances an engine-driven air-compressor to facilitate the inflation of tires. The European industry follows slowly in adopting these practices. Most of the smaller accessories continue to be made by specialty manufacturers who sell in large lots to the car makers and in smaller lots to the retail trade.
Motor wagons and motor trucks did not be gin to be made on a large scale until automobile