14 2 BOILER TESTS. 



The calorimeter test showed that the steam contained 2. 2 per 

 cent, of moisture. The location of this surface is favorable 

 for the deposit of soot and ashes, and it is thereby rendered 

 inefficient for its purpose. 



Boiler No. 33. 

 Kind of boiler, ...... Horizontal return tubular. 



Number used, . . . . . . Two. 



Horse-power (collective, basis 12 sq. ft. ), One hundred and fifty-eight. 



{Two parts Anthracite Lehigh 

 Buckwheat, one part Clear- 

 field Bituminous. 

 Age, ....'... Five years. 



Boiler No. 33 consists of a plant of two horizontal tubular 

 boilers set in one battery of brick work. The general feat- 

 ures of the boiler and the style of setting are similar to those 

 shown in the cut of Boiler No. 6. The boilers are fitted with 

 pipes placed beneath the shell near the side walls, and the feed 

 water is first passed through these pipes. The additional sur- 

 face thus exposed amounted to 180 square feet, and this is 

 included in the quantity given in the table of dimensions. The 

 side walls and top of the bridge wall, as shown in the cut referred 

 to, are provided with perforated tiles for the admission of air 

 above the fuel, and the furnaces are fitted with fire doors of 

 special form, through which a large amount of air is also 

 admitted. The plant is provided with a flue heater consisting 

 of vertical cast iron pipes, arranged in sections and connected 

 together by means of two headers placed outside the brick 

 work, one at the lower end and one at the upper end. The 

 water supplied to the heater enters it through the lower header 

 and leaves it through the upper header. The exterior surfaces 

 of the pipes are kept clean by means of scrapers, worked 

 alternately up and down, and operated by power. This is 

 placed in a direct line between the boilers and the chimney, 

 as indicated in the ground plan given in the following cut. 

 The flue, which is provided for carrying the gases directly to 

 the chimney, lies beneath the chamber which encloses the 

 heater. The area of surface exposed to the heat in this appar- 

 atus is nearly as large as the total area of heating surface of 



