Submarine Appliances And Their Uses
Deep Sea Diving, &c., &c.

Greatest depths attained. The greatest depth at which useful work has been performed by a diver is 182ft. From this depth a Spanish diver, Angel Erostarbe, recovered ^io,coo in silver bars from the wreck of the steamer “ Skyro,” sunk off Cape Finisterre ; Alexandra Lambert suc- ceeded in salving ^70,000 from the Spanish mail steamer “ Alphonso XI I,” sunk in 162ft. of water off Las Palmas, Grand Canary ; W. Ridyard recovered ^5 0,000 in silver dollars from the “ Hamilia Mitchell,” sunk off Leuconna Reef, China, in 150ft. There are in- dividual cases where much larger sums have been recovered, but those mentioned are particu- larly notable by reason of the great depth in- volved, and stand out as the greatest depths at which good work has been done. Professor Dr. J. S. Haldane, F.R.S., and his Colleagues. J.S Haldane,F.R.S.,and his colleagues—Dr. A.E. Boycott,M.D.,and Lieut.Damant, R.N. —have proved, however, that it is quite possible to do serious work at a depth of 210ft. and even more, provided that the stage method of decompression, as per pages 47 to 49, be employed. (See also Paragraph y op Introduction.) I he sponge fishers of the Mediterranean work at a maximum depth of about 150ft., and the pearl divers of Australia at 120ft. But submarine operations on the great majority of the harbour and dock works of the world are conducted at a depth of from 30 to 70ft. 164