190 
ISLAND LIFE. 
[part I. 
country did not consist almost wholly of precipitous snow-clad 
mountains, it would be capable of supporting most of the vegetable 
products of the American coast in the latitude of Bordeaux . 1 
With these astounding facts before us, due wholly to the 
transference of a portion of the warm currents of the Atlantic 
to the shores of Europe, even with all the disadvantages of 
an icy sea to the north-east and ice-covered Greenland 
to the north-west, how can we doubt the enormously 
greater effect of such a condition of things as has been shown 
to have existed during the Tertiary epoch ? Instead of one 
great stream of warm water spreading widely over the North 
Atlantic and thus losing the greater part of its store of heat 
before it reaches the Arctic seas, we should have several streams 
conveying the heat of far more extensive tropical oceans by 
comparatively narrow inland channels, thus being able to 
1 Professor Haughton has made an elaborate calculation of the differ- 
ence between existing climates and those of Miocene times, for all the 
places where a Miocene flora has been discovered, by means of the actual 
range of corresponding species and genera of plants. Although this 
method is open to the objection that the ranges of plants and animals are 
not determined by temperature only, yet the results may be approxi- 
mately correct, and are very interesting. The following table which 
summarizes these results is taken from his Lectures on Physical Geography 
(p. 344) : — 
Latitude. 
Present 
Temperature. 
Miocene 
Temperature. 
Difference. 
1. Switzerland .... 
2. Dantzig 
3. Iceland 
4. Mackenzie River . . 
5. Disco (Greenland) 
6. Spitzbergen .... 
7. Grinnell Land . t . 
47°.00 
54°. 21 
6 5°. 30 
65°.00 
70°.00 
78°.00 
81°.44 
53°. 6 F. 
45°.7 „ 
35°. 6 „ 
19°.4 „ 
19°.6 „ 
16°.5 „ 
1°.7 „ 
69°.8 F. 
6 2°. 6 „ 
48°.2 „ 
48°.2 „ 
55°.6 „ 
51°.8 „ 
42°.3 „ 
16°. 2 F. 
16°.9 „ 
12°. 6 „ 
28°. 8 „ 
36°.0 „ 
35°.3 „ 
44°. 0 „ 
It is interesting to note that Iceland, which is now exposed to the full 
influence of the Gulf Stream, was only 12°*6 F. warmer in Miocene times, 
while Mackenzie River, now totally removed from its influence, was 
28° warmer. This, as well as the greater increase of temperature as we 
go northward and the polar area becomes more limited, is quite in 
accordance with the view of the causes which brought about the Miocene 
climate which is here advocated. 
