In "The Colliery Manager's Calculator" ( third edition 1872 ) and
"The Colliery Manager's Catechism" ( 1876 ) both by W. Fairley
[ I have both these bound together in a single volume "Fairley
on Coal Mining" ], information is given on properties of wooden
supports, and also on cast-iron tubbing for the lining of shafts,
but no mention is made of steel arch supports for colliery
roadways.
Maybe this indicates that steel arches came into use after
1875, say.
Tony Brewis
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