| split switch with graduated risers | A split switch in which the switch rails are gradually elevated by means of graduated riser plates until they reach the required height above the stock rail. |
| split switch with uniform risers | A split switch in which the switch rails have a uniform elevation on riser plates for the entire length of the switch. |
| manganese tipped switch | A split switch in which the head of the tapered rails is cut away in the point portion and manganese steel pieces fastened to the rail to form the point. |
| switch rail or point rail | The tapered rail of a split switch. |
| point rail rise | The elevation of a switch point rail to allow the overhanging part of hollowed out treads of worn wheels to pass over the stock rail. |
| heel slope | The inclination produced in that part of the switch by graduated risers, which reduce the elevation (as the height of the risers decrease) toward the heel of the switch. |
| bottom planing | The cut planed at an angle on the bottom of the base of the switch rail from the point and towards the heel to allow the switch rail to rest on the top of the base of the stock rail when the switch rail is closed. |
| side planing | The cuts made on the sides of the head of the switch rail to form the taper from the full width of head to the point. |
| top planing | The cut made on the top of the head of the switch rail from the point and to approximately the head separation. |
| chamfer cut | The vertical beveling of the gage side of the switch point to produce a sharp edge to prevent wheel flanges striking the switch point. |
| head separation | The point in a tapered switch rail where the head of the rail assumes its full width. |
| point of switch (actual) | The point where the spread between the gage lines of the main track and the turnout is sufficient to allow for a practical switch point. (The standard width of switch point is 1/4 inch.) |
| vertex or theoretical point of switch | The point where the gage line of the switch rail, if produced, would intersect the gage line of the stock rail. |
| stock rail | A running rail against which the switch rail operates. |
| stock rail bend | The bend or set which must be given the stock rail at the vertex of a switch to allow it to follow the gage line of the turnout. |
| heel of switch | The end of a switch rail farther from the point of switch. |
| heel spread | The distance between gage lines at the heel of the switch rails. This has been standardized at 6 1/4 inches. |
| switch angle | The angle included between the gage lines of the switch rail and the stock rail. |
| switch fixtures | The connecting and bearing parts for the rails of a split switch. |
| insulated switch | A switch in which the fixtures connecting or reaching from one rail to the opposite rail are provided with insulation so that an electric track circuit cannot pass through them. |
| detector bar | A strip of metal mounted alongside the track rail and connected with the throwing mechanism of the switch to prevent the moving of the switch under trains. |
| throw of switch | The distance through which the point of switch rails is moved sidewise, measured along the center line of the rod nearest the point connecting the two switch rails, to bring either point against the stock rails. This distance is standardized at 4 3/4 inches. |