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208 they are sufficient in strength and trustworthiness depends very much upon the method of connecting the running gear and spring suspenders or hangers to them.

Many cars have a main frame to which the spring hangers and other parts are attached, and a secondary frame to which the motor and gear-box, &c., are attached. This secondary frame may be, and generally is, so connected, as in the Panhard and the Daimler cars, that the main frame is relieved of the local stresses which result from direct but separate connection of the motor and gear to different parts of the main frame.

The motor and the main clutch shaft must be truly in line, but if these two main parts of the mechanism are separately attached to a weak frame, the frame twists and bends sufficiently to cause trouble with the clutch, because the one part of the clutch is not parallel with the other, and the inner cone only presses locally in the outer cone instead of fitting all round. Clutches used much when this is the case slip most when slipping is least wanted, soon cause much trouble, and only complete refitting and renewal of the cone surface can secure perfect action.

Most frames are made cycle fashion—of round tubes brazed together and with many of the ears and brackets for attachment of other parts brazed on. When the tubes are good and of ample dimensions these frames are good, but harm may so easily be done to the steel tubes by injudicious brazing that it is well to watch the frames carefully at all joints and connections, so that any flaw or any loosened lug may be discovered. When spring hangers or brackets are attached to these frames so that they splay outward or out of the direct line of pressure from bracket to frame, they put a torsional stress on the frame which aggravates the tendency to fracture or loosening. Some of these frames are much narrower than the width between the springs, and the spring hangers are bent or splayed out to reach the springs after the manner of construction adapted in some pony traps, for which it is satisfactory. But for the heavier load and much higher speed of the automobile it is not