Agassis — Albatross Expedition to the Eastern Pacific. 375 



between 100 and 200 fathoms, a drop of 16°. The serial tem- 

 peratures taken at the southern and northern edges of the cold 

 current on the line Manga Reva-Acapulco agreed well with 

 those taken in the same current to the east. 



The samples of the bottom obtained by the soundings taken 

 by the expedition or gathered in mud-bag and in trawl indicate 

 that an immense area of the bottom of the Eastern Pacific is 

 covered with manganese nodules, and that they play an impor- 

 tant part in the character of the bottom, not only in the area 

 covered by this expedition ; the area of manganese nodules prob- 

 ably extends to the northwest of our lines to join the stations 

 where manganese nodules were found by the Albatross in 1899 

 in the Moser Basin, on the line San Francisco to Marquesas. 



This area may also extend south of our lines Callao to Easter 

 Island, and join the line west of Valparaiso where the Chal- 

 lenger obtained manganese nodules at many stations. I do not 

 mean to imply that manganese nodules are present to the exclu- 

 sion of radiolarians and of Globigerinse. It is probable that 

 the layer of nodules are partly covered by them, and by the 

 thick, sticky, dark chocolate-colored mud which is found where- 

 ever manganese nodules occur. 



During this expedition we sounded every day while at sea 

 and developed very fairly that part of the Eastern Pacific which 

 lies to the south and west of the line from Cape San Francisco 

 to the Galapagos and west of a line from Galapagos to Acapulco, 

 limiting an area occupied by the Albatross in 1891. The area 

 developed by us is included by a line 3200 miles in length from 

 Acapulco to Manga Peva and the area north of a. line from 

 Manga Reva to Easter Island and from Easter Island to Callao. 

 ^Ve developed on our line Galapagos to Manga Peva the western 

 extension of the Albatross Plateau, and found it of a depth vary- 

 ing from 1900 to somewhat less than 2300 fathoms in a distance 

 of nearly 3000 miles; about half-way from the Galapagos to 

 Manga Peva we came upon a ridge of about 200 miles in length 

 with a depth of 1700 to 1055 fathoms, dropping rapidly to the 

 south to over 1900 fathoms. I propose to call this elevation 

 Garrett Pidge. 



Our line from Manga Peva to Acapulco continued to show 

 the western extension of the almost level bottom of the East- 

 ern Pacific. In a distance of 3200 miles the depth varied only 

 about 400 fathoms. This great area was practically a mare 

 icognitura. Three soundings in latitude 20° south towards the 

 Paumotus and five soundings in a northwesterly trend from 

 Callao to Grey's Deep, are all the depths that were known pre- 

 viously of this great expanse of water. This existence of the 

 great plateau dividing Barber Basin along the South American 

 coast from Grev and Moser Basins to the west is most interest 



