154 ROl u-TUMBLE ENGINEERING 



SOMETHI\(; ABOUT /'K INSURE 



Now before bringing this somewhat lengthy lectur< 

 a close (for I consider it a mere lecture, a talk with tin- 

 boys), I want to say something more about \ 

 You notice that I have not advocated a very high p 

 sure; I have not gone beyond 125 Ibs., and yet you 

 know and I know that very much higher pressure i 

 ing carried wherever the traction engine is used, and 1 

 want to say that a very high pressure is no gaut; 

 guarantee of the intelligence of the engineer. The less 

 a reckless individual knows about steam the higher \ 

 sure he will carry. A good engineer is never a: 

 of his engine without a good reason, and then he refuses 

 to run it. He knows something of the enormous ; 

 sure in the boiler, while the reckless fellow never thinks 

 of any pressure beyond the 100 or 140 pounds that 

 rauge shows. He says. "Oh ! that that ain't much 

 of a pressure, that boiler is good for 200 pounds." It 

 hn* never dawned on his mind (if he has one) that that 

 140 pounds mean 140 pounds on every square inch in 

 that boiler shell, and 140 on each square inch of tube 

 sheets. He ought to be able to thoroughly appreciate 



