The essentials to a good switch are simplicity, durability, and security. All other considerations must be sacrificed to insure perfect safety. It is true that no form can be adopted that will render switch tenders careful, but there may be much question whether many of the misplacements of switches are not due to the flying over of switches, after they have been correctly placed by the tenders. As switches are now constructed, the tenders get the blame in all cases, right or wrong. Our engravings exhibit the construction of a new kind of switch, differing in some features from anything else of the kind now in use. Everything about it is substantial, and when placed, nothing short of a man at the levers can change it. The movable rails receive their lateral motion through a lever of the ordinary kind, which may be held in place when not in use, by a hasp and lock, as heretofore. The distinguishing feature of the switch is a rock shaft, shown in detail in Fig. 2, with angular projections underlying, and vertical angular projections rising up on either side of each of the movable rails. The rock shaft is operated by a lever upon which the switch tender places his foot, as shown in the larger engraving. When this lever is depressed, the angular projection upon which the rail rests is elevated as shown in Fig. 2. The rail is elevated with it, and released from the vertical angular projections which rise up at the side of the rail in the first position of the. foot lever and lock shaft as shown in Fig. 1. The lateral movement being then made by the hand lever, the foot is removed, when the weight of the rail depresses the angular projection underlying the rail, and the latter drops down between the vertical angular projections above described, after which no lateral movement of the rail can take place until the foot lever is again depressed.
This article was originally published with the title "Improvement in Railroad Switches" in Scientific American 21, 18, 273 (October 1869)