"Pioneer," about igoi. scene unknown. 

 Norrell.) 



{Photo courtesy of Thomas 



seeled by the 8-vvheel engine. The desire to operate 

 longer trains and the need for engines of greater trac- 

 tion to overcome the steep grades of American roads 

 called for coupled driving wheels and machines of 

 greater weight than the 4—2-0. After the introduction 

 of the 4 4 0, the single-axle engine received little 

 attention in this country except for light service or 

 such special tasks as inspection or dummy engines. 

 There was, however, a renewed interest in ^singles'' 



Figure 12. I in "Pioneer" in Carlisle, Pa., 

 1 901. (Photo courtesy oj Thomas Norrell.) 



in the early 1850's because of \V. B. Adams' experi- 

 ments with light passenger locomotives in England. 

 In 1850 Adams built a light single-axle tank locomotive 

 for the Eastern Counties Railway which proved very 

 economical for light passenger traffic. It was such a 

 success that considerable interest in light locomotives 

 was generated in this country as well as in England. 

 Nearly 100 single-axle locomotives were built in the 

 United States between about 1845-1870. These 

 engines were built by nearly every well-known maker, 

 from Hinkley in Boston to the Vulcan Foundry in 

 San Francisco. Danforth Cooke & Co. of Paterson 

 built a standard pattern 4— 2—4 used by many roads. 

 One of these, the C. P. Huntington, survives to the 

 present time. 



The following paragraphs describe the mechanical 

 details of the Pioneer as it appears on exhibition in the 

 Smithsonian Institution's new Museum of History 

 and Technology. 



The boiler is the most important and costly part of 

 a steam locomotive, representing one-fourth to one- 

 third of the total cost. A poorly built or designed 

 boiler will produce a poor locomotive no matter how 

 well made the remainder of mechanism. The boiler 

 of the Pioneer is of the wagon-top, crownbar, fire-tube 



252 



Bl I ! I TIN 240: CONTRIBUTIONS FROM THE MUSEUM OF HISTORY AND TECHNOLOGY 



