57 



been brought up on sounding lines, from the enormous depths of 

 1,000, 1,200, and 1,500 fathoms; but these were looked upon 

 with great doubt, as they might become attached to the line 

 on its passage up. One of the objects of the expedition was to* 

 ascertain whether animal life did really exist 'at great depths. At # a 

 depth of 2,500 fathoms they had found a great number of anjrrfals, 

 belonging to various classes, and from the examination they had 

 made, came to the conclusion that no class of marine animals was 

 excluded, so that the ocean's bed at that depth was not a barren 

 wilderness, as supposed formerly. 



The general condition of the sea bottom was peculiar. In the 

 greater depths there were no pebbles, gravel, or sand, nothing but 

 a fine smooth unctuous mud, which seemed to extend everywhere 

 over the warmer portion of the Atlantic. The surface of the 

 deposit had a creamy look, and consisted of shells of globigerinise, 

 &c. — underneath the surface was found a smooth unctuous matter, 

 made uniform in consistency by pressure, and consisting of the 

 remains of these animals. Thus a bed of limestone was in process 

 of formation. A piece of chalk microscopically examined presented 

 identically the same appearance as this deposit. Dr. Thomson 

 .referred particularly to the differences of temperature existing at 

 various depths, and in different portions of the area under examin- 

 ation, and illustrated this portion of his lecture by diagrams. 

 Reference was also made to the question as to what depth light 

 penetrated; the lecturer remarking that during the expedition of 

 the past year, means were not available for conducting the neces- 

 sary experiments, but that parties were engaged at present in the 

 manufacture of an instrument, which seemed likely to prove 

 suitable for the required purpose. 



He also described minutely the various apparatus used for 

 dredging, sounding, ascertaining the temperature, and for obtaining 

 specimens of the water at various depths for analyses. At the 

 conclusion of the lecture Dr. Thomson exhibited and described a 

 large series of the specimens obtained by dredging — molluscs, 

 echinoderms, corals, crustacean, sponges, &c. — several of the species 

 being new to science. In several of the specimens he pointed out 



H 



