Misc.Accessory Series Coal Sacks Freestanding Trio
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.
To this day sacks are still the standard method of delivering coal to domestic users, even though these are but a tiny fraction of the multitudes relying on coal for cooking and heating up until the mid 20th century. Although they are now made of woven plastic, for most of the period they were made of fabric, usually hessian, and sometimes also creosoted for extra protection.
In the UK the cwt bag was the standard, with a metal disc sewn into a top corner to verify it conformed to the official capacity.
Once coal had been discharged or unloaded from a wagon, the bags would be filled by hand, then loaded onto carts - and later lorries - for delivery: they were always kept open from loading to the point of delivery, unlike most other sacks which were usually fastened.
Here we have three freestanding full sacks, presumably just filled, which have been left in a group ready for stacking or loading.