64 Transactions. — Miscellaneous. 



well as his soundings and dredgings, and observations on cur- 

 rents and sea-temperatures at different depths, threw a flood 

 of new light on the physical and biological conditions within 

 the antarctic circle ; but his ships were unprovided with 

 steam-power, like those of all other antarctic explorers; and 

 this is extremely disadvantageous, because the vessels are 

 unable to make progress during the all-too-scanty periods of 

 fine, calm weather ; contrary winds in ice-encumbered waters 

 are very perplexing and dangerous, and to anchor near an ice- 

 bound coast while exploring parties are sent ashore is too 

 risky for sailing-vessels. 



The " Challenger " is the only steam-vessel that has 

 crossed the antarctic circle, and, as she was not strengthened 

 to bear the blows and pressure of ice, she could do little in the 

 way of exploration through the pack, and was obliged to con- 

 fine the observations to deep-sea soundings. 



Putting together all the various results of the observations 

 that have been made, Dr. Murray has prepared various maps 

 of the southern pole (partially reproduced), in which he has 

 shown what parts of the coast-line of antarctic land have 

 been fixed, and these he has connected by dotted lines indi- 

 cating the probable shape of the great antarctic continent 

 which, from all indications, he presumes to exist, surround- 

 ing the south pole, about 3,500 miles long by 1,500 miles 

 broad, and covered with perpetual snow and ice. He indi- 

 cates also the approximate position assigned to the magnetic 

 pole or poles, and the known and supposititious mean baro- 

 metric pressures — the lowest (28 -Din.) being in February, off 

 Victoria Land, near Mounts Erebus and Terror. From the 

 observed preponderance of southerly winds he assumes that a 

 region of high barometric pressure exists around the South 

 Pole. 



The depths of the ocean, as far as they are known, are 

 also figured, and in his paper he draws attention to the 

 remarkable fact that the temperature at the bottom, even at 

 the depth of over 2,000 fathoms, is not below 33° Fahr., while 

 at the surface it may fall to 29°, and at an intermediate depth 

 may be as high as 40°. The abundance of life now existing 

 in these x\ntarctic-Ocean depths is very notable, and specimens 

 of fossils, apparently of Tertiary age, obtained on Seymour 

 Island by a Norwegian whaler indicate that at one period of 

 the world's history a more genial climate must have prevailed 

 in those regions. 



Dr. Murray's maps further give the oceanic deposits in 

 the different areas of the south polar seas; the ice- limits and 

 currents ; the mean temperatures or isotherms, and the 

 isobars and winds, for February ; the annual mean rainfall ; 

 and the magnetic phenomena (after Neumayer). 



