CHAPTER IX. 



CARE OF THE BOILER. 



The boiler should be examined carefully to see that 

 all the plates exposed to the fire are free from heavy 

 scale and not banked with dirt and mud. If the 

 boiler be an old one, stay bolts and flat surfaces 

 should be examined for breaks and ruptures, and the 

 shell should be tested for thin places caused by the 

 rusting of the metal, by pounding with a hammer. 

 Thin places easily dent under the hammer blows, and 

 if they extend over a large section of the boiler it is 

 unsafe to run even at a very low pressure. 



The position of the gauge glass should be 

 determined so that the engineer may know how much 

 water there is on the crown sheet when the gauge 

 shows an inch or more. This is easily done by 

 removing the hand hole plate at the rear of the boiler 

 after the engine is in a level position. Then open 

 the valves leading to the gauge glass and fill the 

 boiler with water until the crown sheet, which may 

 be readily seen, is covered with the depth of water 

 required; this may be from two to five inches, 

 according to the arrangement of the steam and water 

 space. By noting the depth registered in the gauge 

 glass when the desired depth is obtained, the engineer 

 will have means of knowing just how much water 



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