14 ROUGH-AND-TUMBLE ENGINEERING 



malicious motives, but we regret to say that there are 

 people in this world who are mean enough to do this 

 thing, and not stop at what the boy did uncon- 

 sciously, but after shutting the water in the gauge for 

 the purpose of deceiving you, they then go to the blow- 

 off cock and let enough \\ ater out to insure a dry crown 

 sheet. While I detest a human being guilty of such a 

 irdly trick, I have no sympathy to waste on an en- 

 gineer who can be caught in this way. So, if by this 

 time you have made up your mind never to build a fire 

 until you know where the water is, you will never be 

 fooled and will never have to explain an accident by 

 saying, "I thought I had plenty of water." You may 

 be fooled in another way. You are aware that when a 

 boiler is fired up, or, in other words, has a steam pressure 

 on, the air is excluded, so when the boiler cools down, 

 the steam condenses and becomes water again, hence the 

 space which was occupied by steam now when cold be- 

 comes a vacuum. 



Now should your boiler be in perfect shape, we mean 

 perfectly tight, your throttle equally as tight, your pump 

 or injector in perfect condition, and you were to leave 

 your engine with the hose in the tank, and the supply 

 globe to your pump open, you will find on returning to 

 your engine in the morning that the boiler will be nearly 

 if not quite full of water. I have heard engineers say 



