314 THE PHYSICAL GEOGRAPHY OF THE SEA. 



act of striking the bottom ; it shows how the shot is detached, 

 and how specimens of the bottom are brought up, by adhering to 

 a little soap or tallow,''^ called " arming," in the cup, C, at the 

 lower end of the rod, B. With this contrivance specimens of 

 the bottom have been brought up from the depth of nearly four 

 miles. 



57-i. The greatest depths at which the bottom of the sea has 

 The deepest part of bccu reached with the plummet are in the North 

 the Atlantic Ocean. Atlantic Occau, and the places where it has been 

 fathomed do not show it to be deeper than twenty -five thousand 

 feet. The deepest place in this ocean (Plate XI.) is probably 

 between the parallels of 35° and 40° north latitude, and immedi- 

 ately to the southward of the Grand Banks of Newfoundland. 

 The first specimens have been received from the coral sea of the 

 Indian Archipelago and from the North Pacific. They were col- 

 lected by the surveying expedition employed in those seas. A 

 few soundings have been made in the South Atlantic, but not 

 enough to justify deduction as to its depths or the precise shape 

 of its floor. 



575. The friends of physical research at sea are under obliga- 

 Deep-sea soundings tlous to thc ofiiccrs of the Eufflish navv for much 



by the English -, ^ t - n ■ i-t-- • i 



navy. valuablc iiiiormation toucnmg this mterestmg sub- 



ject. Certain officers in that service have taken up the problem 

 of deep-sea soundings with the most praiseworthy zeal, energy, 

 and intelligence. Dayman in the Atlantic, Captains Spratt and 

 Mansell in the Mediterranean, with Captain Pullen in the Red 

 Sea, have all made valuable contributions to the stock of human 

 knowledge concerning the depths and bottom of the sea. To 

 Mansell and Spratt we are indebted for all we know about deep- 

 sea soundings in the Mediterranean, as we are to Pullen for those 

 in the Red Sea. By their lines of soundings, their maps and 

 profiles, they have enabled physical geographers to form, with 

 some approach toward correctness, an idea as to the orography 

 of the basins which hold the water for these two seas. We are 

 also indebted to the French for deep-sea soundings in the Medi- 

 terranean. That sea appears to be about two miles deep in the 

 deepest parts, which are in the isleless spaces to the west of Sar- 

 dinia and to the east of Malta. 



* The barrel of a common quill attached to the rod has been found to answer 

 b:'ttcr. 



