One can take with him one or more springs ready wound up, for carrying which surplus boxes are attached to the back of the vehicle. When the spring is wound up and the escapement secured, it will retain its energy for years. But as every spring weighs at least nearly eighty pounds, this mode of providing reserve power has its limits. Besides, the changing of the springs is no little trouble. As a rule, a second method is preferred. The Transport Association has a number of station-houses for other purposes, on all the more frequented roads. These stations are indicated by flags, and travellers in the _draisines_ can halt at these and get their springs changed. Every station always has on hand a number of wound-up springs; and so travellers can journey about at any time without let or hindrance, particularly if they are prudent enough to furnish themselves with a reserve spring for emergencies. Such stations exist not merely in and around Eden Vale, but in and around all the towns in Freeland as well as on all the more frequented country roads. And as the different associations carrying on the same industry all over the country were shrewd enough to adopt the same measure for all their springs, it is possible to travel through the whole of Freeland certain of finding everywhere a relay of springs. But if one would be absolutely sure, he can bespeak the necessary springs for any specified route through the agency of his own association; and in this case nothing would prevent him from leaving the highways and taking the less frequented byways so far as they are not too rough and steep--a contingency which, in view of the perfect development of the Freeland system of roads, is not to be feared except among the most remote mountain-paths. In this way, two years ago, our family went through the whole of the Aberdare and Baringo districts, travelling a distance of above a thousand miles, and doing the whole journey most comfortably in a fortnight.'