In the Star, Eagle, and such other types the man is raised upon the obstacle entirely by the large rear wheel, which carries nearly all of the weight, as shown by the height of the curve; it raises beautifully upon the obstruction with little or no check in the momentum, the diverging lines showing about the same distance apart as at the base. It has been thought to be an advantage to reduce the weight upon the front wheel, but the importance is very much exaggerated; it will reduce the impact in dropping down from an obstruction, and will thus cause less annoyance in rough-road riding; still this does not alter the fact that the momentum in the man and part of the machine is not only stopped, but reversed backward, as shown in the diagrams. If the wheel were lifted entirely free from the ground before advancing upon the obstruction, it is obvious, then, that no harmful result would ensue, not so much because the jolt and impact in dropping off is obviated, but for the reason that the momentum forward is not interfered with. If the rider should run full force against a wall with his forward wheel, it would be of little consequence to him whether there was any weight upon it or not; it is not always a question of vertical disturbance or of the action of gravity that is of annoyance to the bicycle rider; it is sometimes better to have a heavy weight upon a wheel if it can be kept in contact with the obstruction, as, for instance, upon the front wheel of the Ordinary when it rolls off, as it will be seen that the curve shows a splendid contour by which to give a good pull on the machine. Fig. 6 shows the Kangaroo type, with a forty-inch front driver and an eighteen-inch rear wheel; this curve presents very little change from that of the Ordinary. Fig. 7 illustrates the Rover type, having two thirty-inch wheels with their centres forty-one inches apart, the saddle forty inches high and twelve inches in front of the vertical through the rear axle. The mere contour of the curve in the last figure mentioned would be somewhat misleading did the diverging lines not show that in the rolling off of the rear wheel the momentum is considerably checked,—that is, the saddle moves more slowly forward than the normal forward pace of the wheels, though there is no direct reversion of the momentum, as occurs in the Ordinary and some others.