CHAP, V. | DEEP-SEA SOUNDING. 929 
and currents, and filling up hollows by drifting about 
and distributing their materials. 
The first careful surveys of the Atlantic, in which 
ereat depths were determined with considerable accu- 
racy, are the cruises of Lieut.-Commanding Lee, in 
the U.S. brig ‘Dolphin’ (1851-52), and of Lieut.- 
Commanding O. H. Berryman, in the same vessel 
in 1852-53; but the sounding voyage in which 
modern appliances were first employed with perfect 
accuracy with a practical object was that of Lieu- 
tenant Berryman in 1856, in the U.S. steamer 
‘Arctic,’ in which twenty-four deep-sea soundings 
were taken with the Brooke’s and Massey’s sounding 
machines on a great circle between St. John’s, New- 
foundland, and Valentia in Ireland, with a view 
to the laying of the first cable. The same ground 
was gone over by Lieutenant Dayman, in H.M.S. 
‘Cyclops,’ in June and July, 1857, and thirty-four 
soundings were taken, the depth being estimated by 
Massey’s sounding-machine and a modification of 
Brooke’s machine already described. The next im- 
portant sounding expedition was that of Commander 
Dayman, in H.M.S8. ‘Gorgon,’ from Newfoundland 
to the Acores, and thence to England. The depths 
were taken in this case with a lead usually 188 Ibs. 
in weight which was lost at each cast, and alba- 
core line with a breaking strain of 420 lbs. Only 
on one occasion, about a third of the way from the 
Acores to England, a cup-lead was let go, attached 
to a stronger line, in 1,900 fathoms, and came up 
half filled with grey ooze. 
Another route for a telegraph cable having been pro- 
posed, H.M.S. ‘Bull-dog’ started in July, 1860, under 
