I've now done some more work on the Radstock colliery accounts and have
found a contract by which the company agreed to supply to a distributor
"25,500 Tons of Best & Brush Coal & 4,500 Tons of Small... Best shall be
passed over and Small shall be passed through a ¾ inch screen" at a price of
"Best 20/6, Brush 19/-, Small 10/6 per Ton of 20 Cwts." I've still got no
idea what brush coal was though. Incidentally, royalties weren't an issue in
the extraction of small coal at Radstock as, apart from a small area
belonging to the church, all the royalties belonged to the mine owner.
As for round coal, I've now discovered that Brian Mitchell, in the glossary
of his book "Economic Development of the British Coal Industry 1800-1914"
defines it as "large lumps" (I told you I should already know this).
In the front of the "List of Mines" for 1938 there's an advert, with
illustrations, for Harco perforated steel and woven wire screens. The
perforated screens consist of steel sheets with a series of slots or round
holes. There's no mention of bar screens.
Keith Ramsey
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