Engineering Wonders of the World
Volume I

RAILWAY SNOW-PLOUGHS. 245 turntable in the right direction for clearing the next leg. Despite these difficulties, how- ever, the entire switchback was cleared in little more than nine hours, and kept open for two days by the single machine. Then a second arrived, and for the rest of the winter a string of four heavy engines, armed at each end with a rotary, continued the work so effectively that not a single train was stalled. In view of these facts it is not surprising that many American, and some European, lines which have to fight snow on a big scale should have adopted the ingenious though simple machine which forms the main sub- ject of this article. The difficulties of its CUTTING THROUGH DRIFTS ABOVE THE TOPS OF THE CARS. task, and the success with which it over- comes them, will be conveyed to the reader by our striking illustrations. LOCOMOTIVE CONSTRUCTION.—IV. DIAGRAM TO SHOW THE PRINCIPLES OF THE ORDINARY STEPHENSON- HOWE REVERSING GEAR. E1, E2, eccentrics; R1, R2, eccentric rods; L, link ; B, block sliding in link and attached to the end of rod which moves in guide, G, and actuates slide-valve, V; P, piston. It will be noticed that the raising or lowering of the link alters the posi- tion of the slide valve relatively to the steam and exhaust (central) ports.