360 siege of the south pole 
anticipated by Sir James Ross had the collection brought 
home by that explorer been fully worked up, and it is the 
completeness with which every scrap of physical and 
biological information obtained by the Challenger was 
subsequently analysed and made use of which chiefly dis- 
tinguishes the expedition from all that went before. 
With regard to one of the specific problems prescribed 
before the Challenger sailed, Sir John Murray pointed 
out, that no fewer than ninety species of animals known 
in the northern seas were also found living south of 
Kerguelen, but had never been reported from any part of 
the tropical seas that lie between the two polar regions. 
For the rest, the study of the deposits showed conclusively 
that the Antarctic continent exists and though, as Cook 
asserted, it is eternally frost-bound it is a real continent 
the rocks of which carried northward by the icebergs and 
dropped on th'e floor of the ocean are of a kind only found 
on continental land. The glaciated rock fragments dredged 
by the Challenger which clearly proved that continental 
land existed within the ice-bound region of the Antarctic 
were gneisses, granites, mica-schists, grained quartzites, 
sandstones, compact limestones, and shales, none of which 
occur in any oceanic island. This is the discovery which 
gives to the voyage of the Challenger its chief geographi- 
cal importance, and it shows how unexpected are the lights 
which scientific research is always throwing on questions 
that seem at first sight very remote. It would be inter- 
esting to conjure up the flood of indignant yet dignified 
eloquence with which old Dalrymple would have over- 
whelmed anyone who dared to make the “ illiberal impu- 
tation ” that his great Southern Continent was to be dis- 
covered by the aid of a microscope in the mud from a 
sounding lead ! 
