Miscellaneous Accessory Series Coal Sacks Empties Folded Pile
The MAS series contains what would be known in Film/Stage/TV circles as 'set dressing' - smaller items added to the overall scene to give it character by adding details of an appropriate locale and period.
Since coal was a staple commodity used by nearly every household in the country, its distribution was officialy regulated: the sacks had metal badges rivetted on to confirm they were of the correct capacity, and they were reused until they wore out. As soon as a load had been delivered each empty sack was folded, stacked and taken back to the yard ready for refilling, and the process would start all over again, so folded piles would be seen both on delivery lorries and also alongside any ongoing bagging operation.