SCIENCE IN THE INDUSTRIAL WORLD 



ferent process the same fibers may be used as a compo- 

 nent of fireproof substances, such as the drop-curtains 

 in the theaters and the packing of engines. By proper 

 manipulating it is made into soft, pliable, felt-like 

 "chamois fiber," or compressed and hardened into an 

 ideal material for car wheels. In short, it can be made 

 to take the place of down, or steel, or almost any other 

 substance of intermediate density. 



When the manufacture of paper car wheels was 

 announced a few years ago it was generally supposed 

 that this was simply the experiment of some imagina- 

 tive enthusiast. Few people took the announcement 

 seriously. But in point of fact the paper car wheel has 

 no rival for endurance and reliability. The cost of 

 manufacture is its principal drawback. The process of 

 making these wheels is as follows: 



"The material used is calendered rye-straw board, 

 or thick paper, and the credit of the invention belongs 

 to Richard N. Allen, a locomotive engineer. The 

 material is sent to the car-wheel shops in circular 

 sheets measuring from twenty-two to forty inches in 

 diameter, and over each of these is spread an even 

 coating of flour paste. The sheets are then placed one 

 above the other until a dozen are pasted together, 

 when all are subjected to a hydraulic pressure of five 

 hundred tons or more. After two hours' pressure, 

 these twelve-sheet blocks are kept for a whole week in 

 the drying-room heated to a temperature of 120 F., 

 after which a number are pasted together, pressed, and 

 dried for a second week; a third combining of layers is 

 then made, followed by a month's drying, until there is 



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