particularly since it is known to have had a number of prior 

 owners. 



It was Warner's opinion, however, that if it had originally 

 been a Philadelphia and Reading engine, it was more likely 

 to have been either the Boston or the J. E. Thayer of Eastwick 

 and Harrison rather than a locomotive built by another 

 firm, of which the Lowell-built Conestoga of 1842 had been 

 considered by some to be the chief possibility. 



At first glance the No. 3 appears much more modern than 

 its actual age, but this is mainly because it has the 4-4-0 

 wheel arrangement with which people today are more famil- 

 iar. The cab, not original, is of a design similar to that used 

 on the Pawnee class of engines first built at the Reading shops 

 in 1852. Also not original are the headlight, the sandboxes, 

 and the truck wheels. Sandboxes worked from the cab were 

 not used in this country prior to 1846; the truck wheels, 30 

 inches in diameter, are of cast iron, manufactured by A. 

 Whitney & Sons of Philadelphia, whose wheel foundry was 

 established in 1846. The smokestack has obviously been 

 altered, if not replaced entirely. 



The No. 3, now an anthracite-burning locomotive, is 

 thought to have been originally a wood burner. The firebox 

 is of the Bury type, which was in common use up to 1850. 



The four driving wheels of the No. 3 are 42^2 inches in 

 diameter, the extreme wheelbase is 178 inches, and the dis- 

 tance between the two driving axles is 551/2 inches. The in- 

 clined cylinders are connected by long rods to the rear 

 drivers. The exact cylinder bore, which had not been known 

 for many years, was measured in October 1954 by represent- 

 atives of the Reading Co. and found to be 12% inches. The 

 stroke is 18 inches. 



The type of reversing mechanism designed by Andrew M. 

 Eastwick in 1835 is thought to have been originally applied, 

 and it is also thought that the original steam chests are still 

 on the locomotive. The old valve gear has been replaced by a 

 double-eccentric motion, the two eccentric rods being respec- 

 tively attached to the top and bottom of a straight link. 

 When the new motion was applied, the old reversing blocks 

 were removed from the steam chests and discarded, the new 

 valves being placed directly on the valve seats. This made it 



68 



