1 . What is the greatest depth of the ocean and where is it? 



According to the latest records, the greatest depth of 37,782 feet was 

 observed in 1962 by the British survey ship COOK in the Mindanao 

 Trench near the Philippines. This spot is now known as the Cook Deep. 

 As long ago as 1927, depths in excess of 35,000 feet in the same area 

 were reported by the German cruiser EMDEN. 



In recent years, many other deeps have been measured by oceanog- 

 raphers; some of those reported by British, Soviet, and U. S. ships 

 follow: 



In 1952, the British survey ship CHALLENGER located a depth of 

 35,640 feet in the Marianas Trench off Guam (the Challenger Deep). 

 This depth was measured by an echo sounder; it took 7-1/4 seconds for 

 the sound to reach the bottom. To confirm the sounding, a weighted 

 cable was lowered to the bottom; this lowering required 90 minutes. 



In 1959, the Soviet vessel VITYAZ reported a depth of 36,200 feet 

 near the Challenger Deep. The Marianas Trench had been sounded in 

 1927 by the Japanese survey ship MANSHU, which recorded a depth 

 of 32,190 feet. 



On January 23, 1960, the bathyscaph TRIESTE descended into the 

 Marianas Trench to a depth of 35,800 feet. 



Although most publicity has been given to the Marianas and Min- 

 danao Trenches, very deep soundings have also been recorded in the 

 Southern Hemisphere. In 1952, the U. S. research vessel HORIZON re- 

 corded a depth of 34,884 feet in the Tonga Trench, south of Samoa 

 Islands. 



Gaskell, T. F. 



World Beneath the Oceans, American Museum of Natural History, 



1964. 

 Soule, Gardner 



The Ocean Adventure, Appleton-Century, 1966. 

 Stewart, Harris B., Jr. 



Deep Challenge, Van Nostrand, 1966. 



