500 KANSAS CITY REVIEW OF SCIENCE. 



just ahead of the fire-boxes. The weight of the boiler is evenly distributed, and 

 by placing the heavy parts of the machine so near the rail a swinging motion is 

 prevented when the engines are in operation. 



In conclusion Mr. Abbe states that 300 pounds pressure will be necessary 

 in the boiler. Now these important questions, he says, arise : Can such piston- 

 speed be used? Can packing be made which will stand such friction and 

 metal bearings which will keep cool ? Can steam be made fast enough with the 

 boiler in such a position? Can men be found to fire such a machine or run it? 

 Will people ride at such a rate of speed ? These, of course, are minor points, 

 however, and easily overcome. The main questions have been solved in this 

 article and rapid transit is now an assured fact. It is to be hoped that Mr. Abbe 

 will hasten to enter into a contract with the projector of the tunnel between Eng- 

 land and America under the Atlantic, so that his ideal express may in the here- 

 after be utilized, not only for trans-continental but for inter- continental travel. — 

 Globe- Democt at. 



STAMPED RAILWAY WHEELS. 



The following account of the manufacture of railway wheels by stamping at 

 the Blast Furnace, Forge and Steel Works, St. Chamond, is from Revue Generale 

 des Chemins de Fer, and was translated in the abstracts of the British Institution 

 of Civil Engineers : " The wheel centre is constructed in three operations — the 

 formation of the rough piece, the rolling into shape and to the diameter, and the 

 finishing off. The processes are a little different for working in iron and in steel. 

 The description applies to a wheel center of the Western Railway having an un- 

 dulated web of about three feet in diameter and weighing 495 pounds. A 

 wrought- iron pile is made up of six layers of bars, eight inches by four wide, cut 

 to a circle twenty inches in diameter, placed between two flat rings of iron, one 

 above and one below the six layers, keeping them in and binding them. Three 

 rings of one and one-half inch square iron, seven or eight inches in diameter, 

 are piled upon the layers as materials for the nave. After the hammering for 

 the first heat, the slab is inverted and three more rings are placed on the other 

 side for the other portion of the nave, and for the second heat. With two more 

 heats, making four heats in all and five or six blows of the hammer in each heat, 

 the forging is completed. The central opening is punched out in the operation 

 of stamping. For the manufacture of steel centers a very mild steel is used, 

 having a tensile strength of from twenty-five tons to thirty tons per square inch, 

 and an extensibility of twenty per cent. A special ingot weighs, for one of the 

 Western wheels, 530 pounds. The work is done in two heats. The ingot is 

 heated, in the course of an hour or an hour and a half, to a white-yellow. It is 

 placed for hammering in the position it occupied in the mold, and any blown 

 holes that may be present in the bloom are likely to be removed in piercing for 

 the nave. Each hammering requires from five to ten minutes; the second heat 



