4-4- an d 4-6-0 Locomotives 51 

 most popular type of big engine which 

 must deal with trains of over 300 tons; it 

 is cheaper to build than the ' Pacific ' 

 type, and whilst it is common on all 

 four groups, at present the " Pacific " is 

 built only on the London and North- 

 Eastern. 



The ' Atlantic " may be regarded as 

 obsolete. None have been built since the 

 grouping, whilst on the L.M.S. the Lan- 

 cashire and Yorkshire type, though not 

 thirty years old, have begun their proces- 

 sion to the scrap heap. 



Until the 'seventies the leading bogie 

 was rarely used on British engines. There 

 was no real reason for this aid to easy run- 

 ning since the express engines up to then 

 had been relatively small. Two typical 

 machines of the pre-bogie era come readily 

 to mind, and as showing the longevity of 

 the locomotive in Britain, it should be men- 

 tioned that specimens of both classes are 

 still at work. The first are the North- 

 Western ' Precedents ", which came out 

 in the early 'seventies, soon after Mr. Webb 



