latest developments of water- tube boilers make avail- 

 able 150 to 200 pounds in stationary and up to 300 

 pounds' pressure per square inch in marine service. 

 Sufficient energy is stored in one of the old-fashioned 

 plain cylindrical boilers at 100 pounds' steam pressure 

 to project it to a height of over 3^ miles. 



A cubic foot of heated water in an ordinary boiler 

 carrying 70 pounds of steam pressure has about the 

 same explosive energy as a pound of gunpowder. 

 That some forms of boilers in use to-day do explode, 

 is witnessed by the sad list of casualties from this 

 cause every year in fact almost daily. 



It is now fully established by the experience of 

 Boiler Insurance Associations in this country and 

 England, that all of the mystery of boiler explosions 

 consists in a want of sufficient strength to withstand 

 the pressure. This lack of strength may be inherent 

 in the original design and construction, but it is most 

 frequently the effect of weakening of iron and steel 

 by strains due to unequal expansion caused by 

 unequal heating of different parts of the boiler, or 

 it may be due to corrosion from long use or im- 

 proper care. 



The first element of safety is ample strength, 

 which can be best attained in connection with thin 

 heating surface by small diameters of parts under 

 pressure. 



The second element of safety is the prevention of 

 strains from expansion or other forces by providing 

 the necessary elasticity. 



The third element of safety is such an arrange- 

 ment of parts that when, through gross carelessness 

 or oversight, the water becomes low and the boiler 

 overheated, a rupture, if it occur, shall be localized 

 and of so small a detail that no serious disaster can 

 follow. 



In addition to being safe, a boiler must be econom- 



, ical and durable. To be economical the heating 



surface must be so disposed that the maximum 



amount of heat shall be absorbed from the heated 



products of combustion by the water in the boiler. 



To be durable, all parts of the boiler must be 

 readily accessible for inspection and cleaning, and 

 must be so assembled and of such material as to be 

 free from excessive strains and deterioration incidental 

 to the various extremes of temperature and to the 

 chemical constituents of the gases and water, which 

 are necessarily characteristic of the process of steam 

 generation. 



With the essential properties of a steam boiler, 



safety, economy and durability, always in mind, 

 The Babcock & Wilcox Company, striving to turn 

 out the best boiler that money could buy, have 

 during the last quarter of a century developed 

 and perfected the Babcock & Wilcox Water-Tube 

 Boiler. 



That the tubular sectional principle of construc- 

 tion, its distinguishing feature, fulfills the require- 



ments of safety has been demonstrated by the fact that 

 there are nearly 6,000,000 II.P. of Babcock & Wilcox 

 boilers in use. 



That they are durable, is witnessed by the fact that 

 practically every Babcock & Wilcox boiler which 

 has been built during the past twenty-five years is in 

 use to-day carrying the steam pressure for which it 

 was designed. 



That they are efficient, is at least indicated by the 

 fact that the entire electric transportation system of 

 the City of Greater New York, including surface, 

 elevated, and subway railroads, the electric service 

 of the New York Central and of the New York, 

 New Haven & Hartford Railroads are all operated 

 from central power stations equipped only with 

 the product of The Babcock & Wilcox Company, 

 as are all of the central stations of the New York 

 Edison Company, which controls the distribution 

 of electric light and power in this city. 



In the basement of the Singer Building there are 

 installed five Babcock & Wilcox sectional water-tube 

 boilers, four having a nominal rating of 400 H.P. 

 each and one having a nominal rating of 325 H.P., 

 or a total of 1,925 H.P. They can in case of neces- 

 sity supply and continuously develop 2,888 H.P. 

 These boilers furnish all of the power required for 

 the operation of the elevators and the various appa- 

 ratus incidental to the maintenance and operation of 

 this great building. 



[87J 



