LIGHT OF OCEAN DEPTHS.

Auckland Star, Volume LXI, Issue 231, 30 September 1930, Page 6

LIGHT OF OCEAN DEPTHS.

Levels of the ocean provided with violetcoloured daylight, like a scene in the theatre, are reported 'by Dr. Henry Fairfield Osborn, of the American Museum of Natural History, as a recent discovery of the expedition now exploring the ocean off Bermuda. Save Dr. E. E. Free's Science": "Dr. William Beebe, leader of the expedition, and Mr. Otis Barton have made fifteen deep-sea dives, Dr. Osborn reports in a communication to 'Science,' some to depths of over 800 feet, , using the new steel diving sphere constructed by Mr. Barton. Windows of clear fused quartz withstood the outside water pressure of over six hundred pounds to the square inch, and permitted Dr. Beebe and Mr. Barton to look out. Close to the sea's surface, they found, the light was ordinary daylight, but as the sphere descended all red and yellow colours of the spectrum faded out completely. Next the ; blue colours faded, leaving nothing Jbut the pure violet rays at the extreme end of the spectrum where the wave lengths of light are shortest. At depths of 700 feet and below the outside world of water etill seemed to glow dimly with theee extreme, almost colourless, violet rays. The effect i 3 due, physicists explain, to the action of tiny suspended particles in the upper layers of the water, and even of the water molecules themselves, in absorbing the rays of the Ted and yellow end of the spectrum while allowing eome of the violet rays to pase."