rail crash at Shrewsbury, England, 1907

The mail sorters' van - perhaps an explanation for the recipient of why the sender's previous postcard didn't arrive?

On 15 October 1907 an overnight sleeping-car and mail train of the L.&N.W.R. from Manchester to the West of England derailed on the sharply-curved approach to Shrewsbury station, killing 18 people and injuring 33 more. Excessive speed was the cause: the train speed was estimated at 60 mph (97 km/h) on a curve limited to 10 mph (16 km/h). The train was hauled by L.&N.W.R. Experiment class 4-6-0 number 2052, Stephenson.

For details of lots of railway accidents in Australia and NZ, see the books Australian Railway Disasters and Danger Ahead respectively.