Casgliadau Arlein

Blueprint, white text on blue paper. A line graph with the title: 'THE BRITISH THOMPSON HOUSTON COY. LTD / Q.3472 - 26-3-19 / SOUTH WALES / HICK - BREGUET EJECTAIR. / CURVE SHEWING VACUUM OBTAINED WITH VARYING / QUANTITIES STEAM WITH CONSTANT SUPPLY & TEMP. / CIRCULATING WATER.' Contained within a moroon hardback file with all other documents under accession number 85.184I/4.