ICEBERGS 



Effect of Expansion of Water in Freezing.— Classes of Ice-Fields.— Orit^in of Ice-Floes. — 

 Migrations of Icc-Fioes. — Origin of Icebergs. — The Greenland (llacier. — Annual 

 Product of Icebergs ; their Voyages ; their Effect on the Ocean ; the Order of their 

 Movements ; their Decay ; their Gener.d Influence on Climate. — Transportation of 

 Rock Debris by Icebergs. — Effect of lee on Shores. — Iceberg Work in Former 

 Geological Periods. — Dangers to Ships from Collision with Icebergs. 



Much has been said by optimists concerning; the many 

 advantages which arise from the simple but most exceptional 

 fact that, while all other substances contract, water expands in 

 passing from the fluid to the solid state. The consequences 

 of this peculiarity are indeed not overstated by those who 

 take an excessively pleasant view of man's relations to the 

 world about him, for the simple reason that it is not easy to 

 exaeeerate the beneficial effects which arise from them. If 

 water did not depart from the general law that substances 

 occupy less space in their solid than in their liquid form, the 

 ice on our seas and lakes would, as fast as it formed, sink to 

 the bottom, so that all the oceans and other water-basins in 

 high latitudes would normally be frozen to their floors, except 

 when the summer's heat had melted a thin hu'cr next the 

 surface. If it were really worth the while to theorize con- 

 cerning things which are out of the present order of nature, 

 we might easily show that such a condition of affairs would 

 make the earth essentially unfit for the uses of civilization. 

 It will, however, be more profitable to consider the points 

 which the pessimist might take, if his ever-smiling adversary 



