10 THE DEPTH AND MARINE DEPOSITS OF THE PACIEIC OCEAN. 



mica being also present ; fragments of a well-rounded pebble of black chert, traversed by 

 microscopic quartz veins. 



" How these pebbles, having all the characteristics of glacial-worn pebbles, came to be 

 carried to this point is an interesting question. As the sharks' teeth and cetacean bones 

 found in the red clay seem to indicate that since tertiary times there have been but very 

 insignificant deposits at great distance from continental areas, similarly we may be tempted 

 to assume that these pebbles, which could not have been transported to their present 

 locality by any agency of the present epoch, were carried to it during the glacial epoch, 

 the thin coating of manganese indicating how small have been the bottom deposits since 

 the glacial period." . . . 



" We could find no spherules of cosmic iron iu the few samples of 

 manganese nodules which we ground to powder. . . . 



"At Station 13, in 2690 fathoms, lat. 9° 57' N., long. 137° 47' W., 

 . . . the ' Blake ' trawl came up full of large manganese nodules, balls 

 varying in diameter from 4| to over 6 inches ; a few of the largest measured 

 6i inches in diameter. . . . The manganese nodules were all more or less 

 mammary ; this is specially well-developed in the flat pieces. . . . 



" At Station 31, in 2700 fathoms, lat. 12° 20' S., long. 144° 15' "W. Red 

 clay. The sea being a little too heavy for a successful haul, the ' Blake ' 

 trawl came up with the net badly torn ; it must have had too heavy a load 

 of manganese nodules, as the part of the bag left contained about a plate- 

 full of small, irregularly shaped nodules, incrusting also volcanic rock. . . . 



"At Station 73 we lowered the trawl in 807 fathoms, lat. 17° 27' S., 

 long. 149° 32' W. It brought up a mass of fine volcanic mud filled with 

 sticks and leaves and decayed vegetation, fragments of rocks and other tel- 

 luric material, pieces of sugar cane, and fragments of cocoanut shells. . . . 



"At Station 133 we lowered the trawl in 742 fathoms, lat. 18° 05' S., 

 long. 142° 23' W. . . . The trawl came up in pieces ; the pocket of the 

 bag contained a piece of obsidian as large as a hen's egg, a piece of pumice 

 and of coral, both coated with manganese, a few fragments of wood simi- 

 larly coated, a fragment of Tubipora, also coated, and a mass of Globigerinse 

 connected by manganese, as well as volcanic fragments and particles of 

 manganese. 



"At Station 134, in 807 fathoms, lat. 18° 06' S., long. 142° 24' W. . . . 

 We sent the swabs down ; brought up . . . some small manganese nodules 

 and sharks' teeth. . . . 



"At Station 173, in 2440 fathoms, lat. 18° 55' S., long. 146° 32' W. . . . 

 The ' Blake ' trawl brought up about half a ton of flattened manganese 



