Casgliadau Arlein

A diagram and three printed photographs of the Gibbs oxygen breathing apparatus 2 hour type, that have been cut out and stuck onto a piece of blank paper. The diagram is printed in black ink on white paper, with explanatory text alongside. The photographs are printed in black ink on white paper, showing a man wearing the Gibbs breathing apparatus from three different angles. Document 88.98I/3 (1) to (4) were originally contained within an acidic card file.