64 



KNOWLEDGE ♦ 



[Jdlt 1^ 1884. 



Day Sign for the Month. 



ZODIACAL MAPS. 



By Richard A. Proctob. 



WE give this week both the day sign and the night sign 

 for the month, one showing the zodiacal sign now 

 high in the heavens at midnight, the other showing the 

 region of the zodiac athwart which the sun pursues his 

 course at this part of the year. 



THE ANTARCTIC REGIONS. 



By R. a. Proctor. 



(Contitmed from page 31.) 



THE enormous icebergs which come from out the Ant- 

 arctic seas suggest interesting conclusions respecting 

 regions as yet unexplored. This will be understood when 

 it is remembered that all the larger and loftier icebergs 

 have in reality had tbeir origin in immense glaciers. Vast 

 masses of ice are formed, indeed, in the open sea. Each 

 winter the seas which have been open during the summer 

 months (December, January, and February) are covered 

 over with ice of enormous thickness, and when summer 

 returns the ice-fields ihus formed are broken up, and the 

 fragments, borne a'jninst each other during storms, become 

 piled into gigantic masses. But the agglomerations thus 

 formed, vast though they are, are far exceeded in magni- 

 tude by the true icebergs. " Among the drifting masses 

 of flat sea-ice," says Tyndall, " vaster masses sail which 



spring from a totally different source. These are the ice- 

 bergs of the polar seas. They rise sometimes to an eleva- 

 tion of hundreds of feet above the water, while the height 

 of ice submerged is about seven times that seen above." 

 " What is their origin 1 " he proceeds, speaking of those 

 met with in the northern seas. " The Arctic glaciers^ 

 From the mountains in the interior the indurated snows 

 slide into the valleys, and fill them with ice. The glaciers- 

 thus formed move, like the Swiss ones, incessantly down- 

 wards. But the Arctic glaciere reach the sea, and enter 

 it, often ploughing up its bottom into submarine moraines. 

 Undermined by the lapping of the waves, and unable to- 

 resist the strain imposed by their own weight, they break 

 across, and discharge vast masses into the ocean. Some o£ 

 these run aground on the adjacent shores, and often main- 

 tain themselves for years. Others escape, to be finally 

 dissolved in the warm waters of the ocean." 



It is important to notice that the Antarctic icebergs are- 

 vaster and more numerous than those formed in Arctic 

 seas. How large these last are will be understood from 

 the instance referred to by Tyndall, who, citing Sir Leopold. 

 MacCliutock, describes an Arctic iceberg 250 ft. high, and 

 aground in 500 ft. of water. But Captain Maury speaks 

 of Antarctic icebergs in the open sea, hundreds of feet 

 high and " miles in extent." '" The belt of ocean that en- 

 circles this globe on the polar side of fifty-five degrees south 

 latitude is never free from icebergs," he adds ; " they are 

 formed in all parts of it all the year round. I have en- 

 countered them myself as high as the parallel of thirty- 

 seven degrees, . . . and navigators on the voyage from the 



