Above these bars, and at right angles thereto, is a rock-shaft F, mounted in bearings G G, so that it is longitudinally-movable a limited distance, to shift the selector lever H from one bar A to the other bar B. SHIFTING LEVER.--The selector I has two fore and aft slots J K, these slots being of such width that the gear shifting lever L can travel therein back and forth. Midway between the ends of the bar the intermediate wall of the selector plate has a cut-out portion as at M, so the lever may pass through. This opening, or gate-way, is in such a position, relative to the cross lots N O, of the bars A B, that when the lever is in line with the gate-way, the slots N O are also in line, and in a neutral position, so that when a lateral motion is imparted to the lever L, and the rock-shaft F is moved longitudinally, the selector lever H will then engage with the other bar. SPEED SELECTORS.--The selector I, in Fig. 52, while made substantially the same in all cars, has a different order of lever movement. Each manufacturer has his own preferential type. In some cases the lever must be thrown forward in order to reverse, and in others it is drawn back. In certain cars the lever is moved forwardly to throw the gears into first, or low, while a number of makers insist that the first movement should be to the rear. [Illustration: Types of Speed Selectors. Fig. 53. 3-Speed. Fig. 54. 3-Speed. Fig. 55. 3-Speed. Fig. 56. 4-Speed. Fig. 57. 4-Speed. Fig. 58. 4-Speed. Fig. 59. 4-Speed.] This is, really, an immaterial matter, so long as there is no standard, and each claims some distinctive feature of value for his particular choice. 3-SPEED SELECTORS.--Figs. 53, 54 and 55 show the 3-speed selectors, in each of which the reverse is brought about by moving the lever to the forward end of the selector. In Figs. 53 and 54 the lever slot, for reversing, is in the inside, whereas in 55 it is in the outside slot. The form 53 also has, in certain makes, the reverse at the rear end of the selector. 4-SPEED SELECTORS.--The greatest variety is found in the 4-speed types, represented by Figs. 56, 57, 58 and 59, the almost universal plan being to place the reverse in the single side slot, as shown in Fig. 56. [Illustration: Fig. 60. Control-Lever Bracket.] One of the most practicable and easily operated selectors is shown in Fig. 60, which is used on the Jeffery car. CONTROLLING THE SELECTOR.--It will be seen, on examination of the selector, that if, in starting, the lever is at its neutral position, as it should be, and it is moved inwardly the distance of about an inch, it will be in position where it can be moved forward to the _first speed_ position. The clutch of the car may then be disengaged gently, by pressing the foot down slowly, and at the same time pressing the accelerator with the right foot, so as to increase the speed of the motor sufficiently to take care of the load.