Rare Davis Submarine Escape Apparatus by Siebe Gorman & Co Ltd. London from the 1930's.

This device was invented by Sir Robert Davis, head of Siebe Gorman, to prevent anoxia and long overpressure illness for divers ascending fast through water. It "adjusts" the pressure in the lungs to the decreasing underwater pressure when the depth decreases. It was invented in 1910 and was adopted by the Royal Navy around 1927. They used it till the 1950's with limited success at several sunken submarines, for example the HMS Poseidon (1931), HMS Thetis (1939) and HMS Perseus (1941).  

The DSEA for sale here is still in the original box. It shows some ageing. For a good working of the apparatus a canister of barium hydroxide and a compressed oxygen were also necessary. These are not present of course.

We haven't tested it!

Take a good look at the photos for a good impression!

The dimensions of the box are 47 x 40 x 11cm. and the total weight is around 4.5 kgs.