Report of tee Committee on Steam Boilers. 79 



Determining the weight, in pounds, of water evaporated per square 

 foot of heating surface per hour, we get, as a measure of the steaming 

 capacity : 



Boot 2 . 65 



Allen 3.59 



Phleger 2.83 



Lowe 3.10 



Blanchard 1 . 92 



It is but right to remark here that, as is indicated by the log, the 

 fires in the Root boiler were allowed, at one time, to get much too 

 low, and it is supposed that the standing of that boiler was thus 

 seriously impaired. The fires of the Lowe boilers were undisturbed 

 during the whole trial, its position, also, being thus lowered. 



The quantity of heat per pound of combustible, as above deter- 

 mined, being divided by the latent heat of steam at 212° Fahr. 

 (966°. 6), gives, as the equivalent evaporation of water at t/ie pressure 

 of the atmosphere, and with the feed at a temperature of 212° Fahr. : 



Root 10 . 64 



Allen 10 . 60 



Phleger 10.49 



Lowe 10.40 



Blanchard 11 . 34 



For general purposes, this is the most useful method of comparison 

 for economy. 



The above figures afford a means of comparison of the boilers, 

 irrespective of the condition (wet or dry) of the steam furnished by 

 them. All other things being equal, however, the committee con- 

 sider that boiler to excel which furnishes the dryest steam ; provided 

 that the superheating, if any, does not exceed about 100° Fahrenheit. 



In this trial the superheating, was as follows : 



Root 16°. 08 



Allen \ 13° .23 



Phleger 0° . 



Lowe 0°. 



Blanchard. .' 0° . 



As the Blanchard, Phleger and the Lowe boilers did not super- 

 heat, it becomes an interesting and important problem to determine 

 the quantity of water carried over by each with the steam. This we 

 are able, by the method adopted, to determine with great facility and 

 accuracy. 



