4 
CRUISE OF H.M.S. CHALLENGER. 
the Government a project for extended investigation, 
which was eventually approved of, and a committee 
appointed to prepare the plans of operation. 
It was suggested that a vessel should be fitted out 
for a three or four years’ cruise, during which time 
sounding, dredging, thermometric observation, and 
chemical examination of sea-water should be carried 
on continuously, with a view to a more perfect 
knowledge of the physical and biological conditions 
of the great ocean basins, of the direction and 
velocity of the great drifts and currents, of the 
faunae of the deep water, and of the zoology and 
botany of those portions of the globe which are at 
present comparatively unknown. 
H.M.S. Challenger , a spar-decked corvette of 2000 
tons displacement and 400 horse-power, was se- 
lected to carry out these recommendations ; and 
the necessary alterations to fit her for the service 
on which she was to be employed were made in the 
dockyard at Sheerness. With the exception of two 
64-pounders, all the guns on the main deck were re- 
moved, so as to obtain the required accommodation. 
In addition to cabins for the Captain, Commander, 
and Director of the Scientific Staff, there were 
spacious compartments for surveying operations and 
analysing purposes, a laboratory for the chemist, and 
a studio for the photographer, all fitted with every 
appliance which skill and science could suggest. On 
the upper deck stood an 18-horse double-cylinder 
