FOSSIL REMAINS. 355 



character of extinct plants and animals which we find buried 

 one above another in the successive strata that compose the 

 crust of the globe. These have in modern times been investi- 

 gated with sufficient care and knowledge of the subject to 

 render it almost certain that successive changes, from extreme 

 to moderate heat, have taken place in those parts of the 

 northern hemisphere which constitute central and southern 

 Europe ; and although we are not yet enough acquainted with 

 the details of the geology of the arctic regions to apply this 

 argument to them with the same precision and to the same 

 extent as to lower latitudes, still we have detached examples 

 of organic remains in high latitudes sufficient to show the 

 former existence of heat in the regions where they are found — a 

 few detached spots within the arctic circle, that can be shown to 

 have been once the site of extensive coral reefs, are as decisive 

 in proof that the climate in these spots was warm at the time 

 when these corals lived and grew into a reef, as, on the other 

 hand, the carcass of a single elephant preserved in ice is de- 

 cisive of the existence of continual and intense cold ever since 

 the period at which it perished. We have for some time 

 known that in and near Melville Island, and it has been ascer- 

 tained by Captain Beechey's expedition, that at Cape Thomp- 

 son, near Beering's Strait, there occur within the arctic 

 circle extensive rocks of lime-stone containing many of the 

 same fossil shells and fossil corals that abound in the carbo- 

 niferous lime-stone of Derbyshire: the remains of fossil ma- 

 rine turtles also (chelonia radiata) have been ascertained by 

 Professor Fischer to exist in Siberia. These are enough to 

 show that the climate coidd not have been cold at the time 

 and place when they were deposited ; and the analogy of ad- 

 jacent European latitudes renders it probable that the same 

 cooling processes that were going on in them extended their 

 influence to the polar regions also, producing successive re- 

 ductions of temperature, accompanied by corresponding 

 changes in the animal and vegetable creation, until the period 

 arrived in which the elephant and rhinoceros inhabited nearly 

 the entire surface of what are now the temperate and frigid 

 zones of the northern hemisphere. 



