CATALOGUE OF THE MECHANICAL ENGINEERING COLLECTION. 87 



on the comparatively few railroads bandling minerals and other heavy freight 

 over steep grades, the eight-wheel locomotive, known for excellence as the 

 American locomotive, was regarded as an ideal engine for hauling both pas- 

 senger and freight trains. In 1870 probably 85 per cent of the locomotives at 

 work on the American continent were of that type. Until the troublesome prob- 

 lem of how to move passenger and freight trains at the least possible expense 

 became dominant in railroad counsels the American locomotive left nothing to 

 be desired as railroad motive power. 



The engine was the product of natural evolution, the survival of the fittest, 

 and altogether admirable as a power producing motor. Lest this book be read 

 when the American locomotive becomes classed with the dinosaurs, I may ex- 

 plain that it belonged to what is now denominated as the 4-4-0 class, having a 

 four-wheel truck under the smoke box and two pairs of coupled drivers in front 



-WINANS LOCOMOTIVE FOR INCREASED ADHESION, I80I. 



and one pair behind the fire box. During the period of this engine's glory a deep 

 fire box passed down between the frames and was compactly bounded by driving- 

 wheel'axles and coupling rods. About one-third of the total weight was gen- 

 erallv carried on the leading truck. , , , „„ 



The perfecting of this form of locomotive represents the most valuable en- 

 gineering work performed on railroad motive power. The work of Evans, 

 Trevithick, Hedlev, Stephenson, Hackworth, Cooper, Baldwin, Dripps, ^\ inans, 

 Harrison Eddv, MillhoUand, Rogers, Cooke, and Mason all produced contri- 

 butions to the 'perfecting of the American locomotive, and very of ten the per- 

 manent gift of what is regarded as a fertile inventor will be ulentihed as a 

 very small part of that finished machine. We find the first groping toward a 

 locomotive machine was a portable boiler with various accessories attached, 

 such as cylinders and wheels. Then came an arrangement of rectangular beams 

 forming a frame which carried the boiler and provided conveniences for hold- 

 in- the four wheels that carried the whole combination of power generating 

 and transmitting appliances. For the track's sake the carrying burden is dis- 



