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Amgueddfa Cymru
Mining Technology - Journal of the Institution of Mining Electrical and Mining Mechanical Engineers, Volume 66, No. 763, May 1984. Booklet - printed in black ink on white paper. The front cover contains an advert for Calvox III signalling equipment, printed in black and blue ink. Inside, there are two leaflets (loose). One is for the Mining 85 conference, 10-12 June 1985 at the NEC in Birmingham, and the other is for the third international congress and exhibition on mine ventillation, 18-20 June 1984 at Harrowgate.
