After many Vauclain compounds had been built in the USA, the Erie received three four-cylinder cross compound Atlantics in 1905. These were the numbers 535 and 536 built by Baldwin and designated class E-4 which are shown here, and the number 537 built by ALCO-Schenectady and designated class E-5. They had their high pressure cylinders on the inside and low pressure cylinders on the outside.
With the general demise of compound locomotives in the USA, both were superheated and simpled in 1916 in the Erie's Hornell shops. In this process the boiler pressure was reduced from 225 to 200 psi, but the tube heating surface was only reduced moderately. After 536 was retired in 1942, 535 became the last Atlantic in service with the Erie when it was retired in 1947.