3i8 NATURE AND MAN. 



and south course through the tropical Pacific. From Tahiti she 

 proceeded south-east towards Cape Horn, with a detour to Val- 

 paraiso ; and after passing through the Straits of Magellan, touch- 

 ing at the Falkland Islands, and putting in at Monte Video, she 

 proceeded eastward halfway across the South Atlantic, to com- 

 plete the east and west section partly taken in the first year of 

 the voyage on the parallel of the Cape. Changing her course to 

 the north, she ran a north and south line as far as the equator, 

 in the meridian of Madeira ; and then, turning north-west, and 

 keeping at some distance from the African coast, got into the 

 middle line of the North Atlantic, which she followed past the 

 Azores ; after which she bore up for home. 



At each of the observing stations a sounding was taken for 

 the determination of the exact depth ; the bottom-temperature was 

 accurately ascertained ; a sample of bottom-water was obtained 

 for chemicai and physical examination ; and a sample of the 

 bottom itself was brought up, averaging from one ounce to one 

 pound in weight. At most of the stations, serial temperatures 

 also were taken ; i.e. the temperature of the waters at several 

 different depths between the surface and the bottom was deter- 

 mined, so as to enable " sections " to be constructed, giving what 

 may be called the thermal stratification of the entire mass of 

 ocean-water along the different lines traversed during the voyage, 

 and samples of sea-water were also obtained from different depths. 

 At most of the stations a fair sample of the bottom-fauna was 

 procured by means of the dredge or trawl : while the swimming 

 animals of the surface and of intermediate depths were captured 

 by the use of a "tow-net," adjusted to sweep through the waters 

 in any desired plane. And while the direction and rate of any 

 surface-current were everywhere determined by methods which 

 the skilful navigator can now use wath great precision, attempts 

 were made to determine the direction and rate of movement of the 

 water at different depths, wherever there was any special reason 

 for doing so. In addition to all this, which constituted the 

 proper work of the expedition, meteorological and magnetic 

 observations were also regularly taken and recorded. 



The vast mass of accurate information, and of materials from 

 which accurate information may be obtained, which has thus been 



