Casgliadau Arlein
Amgueddfa Cymru
Chwilio Uwch
Collection of tech. drawings re pit props
Engineering Drawing National Coal Board, South West Division, roof control department Showing need for special supports at roadheads in highly inclined seams
Pwnc
Diwydiant
Rhif yr Eitem
87.156I/7
Mesuriadau
Meithder
(mm): 436
Lled
(mm): 370
Nid yw sylwadau ar gael ar hyn o bryd. Ymddiheuriadau am yr anghyfleustra.