18 THE ATLANTIC. [ CHAP. 1. 
interested, across the Atlantic Ocean. Ingenious contrivances 
were suggested and applied, not merely for determining the 
exact depth, but for bringing up samples of the bottom suffi- 
cient to test the composition and character of the deposits in 
process of formation on the sea-bed. 
In the mean time another class of students, working for the 
increase of knowledge, though perhaps with less immediate 
bearing upon the progress of the human race or the advance 
of their own interests, had been investigating the forms and’ 
natures of living things, the external conditions upon which 
their frail lives depend, and the laws under which they are 
localized or distributed upon the surface of the earth; and, 
judging from the scanty data laboriously accumulated with the 
imperfect appliances at that time at their disposal, had come to 
the conclusion that life at the bottom of the sea was confined to 
a narrow border round the land; that at a depth of 100 fathoms 
plants almost entirely disappeared and animals were scarce, and 
represented those animal groups only which are among the most 
simple in their organization; while at 300 fathoms the sea-bot- 
tom became a desolate waste, the physical conditions being such 
as to preclude the possibility of the existence of living beings. 
Samples of the sea-bottom, procured with great difficulty and 
in small quantities from the first deep soundings of the Atlan- 
tic, chiefly by the use of Brooke’s sounding-machine, an instru- 
ment which by a neat contrivance disengaged its weights when 
it reached the bottom, and thus allowed a tube, so arranged as 
to get filled with a sample of the bottom, to be recovered by 
the sounding-line, were eagerly examined by microscopists ; and 
the singular fact was at length established that these samples 
consisted, over a large part of the bed of the Atlantic, of the 
entire or broken shells of certain foraminifera, and the bulk of 
the evidence seemed to be in favor of the animals which in- 
habited these shells having lived in the situation in which they 
were found, and not, as was at first supposed, having lived in 
