SIX MILES DEEP

Evening Post, Volume CXIII, Issue 18, 22 January 1927, Page 16

SIX MILES DEEP

PLUMBING THE OUTER OCEANS.

Considerable interest has been caused by the report that the Japanese naval surveying ship Manshu recently obtamed ii sounding of 31,000 feet between Izu and the Bonin Islands; and it ha s been stated that this is the deepest known, spot in the .Seven Seas easily beating tie famous Tusearora Deep of 27,900 feet which was named atter the American warship which' made the sounding (declares the London "Daily News"). The new sounding certainly does beat this, but it is itself beaten by two others. .The Crerman surveying ship, Planet, ' in f»l4 got bottom at 32,112' feet east of the Phillippine Islands, while the Manshu herself, surveying in August, 1924 failed to find bottom with 32,046 feet of wireout. >" " ■■■"

It is interesting to note that, whereas there, are quite a number of elaborate sounding machines on the marketmachines which register the depth of water by the compression,'of air in a sensitised" tube—which are used by all liner.3, it is still' necessary,. when it cSmes to great depths like' this, to employ the same method that was employed by the Vikings and Phoenicians: a' heavy: weight on the end of a line; "■.•■■■.'•

Nowaday a the line is the finest piano wire, but when' Boas was surveying the Weddell Sea 'he used an ordinary cod line; which was .constantly breaking. On one occasion he reported 4000 fathoms—24,ooo feet—and no bottom, which was regarded as a. wonderful sounding." Unfortunately,'it was afterwards proved that his men failed to notice the slight check on the line which told that the weight had hit the bottom' of the sea, and had continued to allow the line to run out by its own velocity) and by the tide. Actually there, was 2660 fatuoma of water in thii t£)t&.s ;•■■■' ■■■•■■■■-