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Indiana University Studies 



Erection. — We will, if desired, supply the services of a man, to super- 

 intend the erection of the iron work, his wages at the rate of six dollars per 

 day, traveling expenses and board from plant and return to be paid by the 

 purchaser. 



Boiler Power. Altho it is a misnomer to speak of the horse- 

 power of a boiler, it has come to be very general among engineers 

 to rate boilers on the amount of steam they are capable of fur- 

 nishing. The ability of a boiler to generate steam depends upon 

 the area of its effective heating surface. Heating surface has 



/<f-^" 



Water-Tube Boiler 



been defined as boiler surface, either shell or flue, which has hot 

 gases on one side and water on the other. The surfaces which 

 have steam on one side and water on the other are called super- 

 heating surfaces. A boiler horse-power is taken as the equivalent 

 of the evaporation of 34}^ pounds of water per hour from a 

 temperature of 212 degrees Fahrenheit to steam at atmospheric 

 pressure. This is sometimes stated as the evaporation of 30 

 pounds of water at 212 degrees Fahrenheit to steam at 70 pounds 



