Note the Cambrian Railway oil lamp cases positioned high above the footbridge.

Peter Kerslake says "After assuming reponsibility for the Cambrian network in 1921 the G.W.R. was obliged to continue with the use of former Cambrian absorbed locomotives, supplementing these with those members its own Duke class, Dean Goods and the like still in service until the Dukedogs appeared in 1936.
This is the eastern side of Machynlleth station , so 3271 is heading on the " up " line towards Cemmes Road and onwards to Welshpool and possibly Shrewsbury with its local stopping service made up of Clerestory roofed stock with what appears to be a Brake in the middle .
This footbridge still appears intact in images from here in the mid 1950s, with many of the original Cambrian station buildings on the left, or Down platform also surviving into the 1970s"