154 



BOILER TESTS. 



coal, and this quality doubtless has something to do with the 

 high flue temperature. 



Boiler No. 38. 



Kind of boiler. Horizontal return tubular. 



Number used, . . . . . .One. 



Horse-power ( basis 12 square feet), . Thirty. 



Kind of coal, , ... Anthracite Wilkesbarre broken. 



Age, One year. 



Boiler No. 38 is a horizontal 

 tubular boiler arranged for 

 superheating the steam, and 

 its general features are shown 

 in the following cuts. The 

 steam-heating surface is here 

 obtained by filling the steam 

 space above the water line with 

 tubes. The products of com- 

 bustion, after passing through 

 the lower tubes in the usual 

 manner, return through the 

 superheating tubes, and enter 

 the chimney from the rear end* 

 The steam on leaving the boiler 

 enters a vertical drum 30 

 inches in diameter and 8 feet high. The draft was produced 

 by a blower which discharged under the grates. 



BOILER 38, LONGITUDINAL SECTION. 



