From Carl Weber's collection comes this image of B&M class P-3a 4-6-2 No. 3709, which an anonymous photographer snapped at Boston on August 19, 1953. Engines in this group had 2992 square feet of evaporative heating surface and 786 square feet of superheater surface, plus a grate area of 53½ square feet. They had booster-equipped trailing trucks, evident from the booster exhaust pipe extending over the smokebox to the stack, but information is not forthcoming regarding the extra starting tractive effort the booster supplied. For additional specifications consult the previous page for No. 3700. No. 3709 went to the scrapyard in 1955.