W. Hopkins on Changes of Climate. 79 
sidering. Its course would be very nearly, but not exactly, east 
and west, reaching a rather lower attitude in Asia thamin America, 
in consequence of the high tablelands of southeastern Asia, 9) 
three succeeding existing isothermals to the north on 
Dove’s map (those for 23°, 14°, and 5° F’.) are very nearly paral- 
lel to that of 32°, and equidistant from each other through about 
of long. in Asia, and through 30° of long. in N. America. In 
the intermediate space they are inflected to the north by the 
Atlantic. Their position in our present hypothetical ease would 
doubtless be approximately determined by substituting straight 
ines across this intermediate space, for the actual inflected lines. 
~The present winter isothermals, north of those just mentioned, 
ie more irregular in their course in eastern Asia, as well as 
in North America. In the former region the distance of sneces- 
north pole, inclines considerably towards north-eastern Asia. 
This position must be due, in great measure, I conceive, to the 
influence of the North Sea, warmed as it is by the Gulf-stream. 
i our hypothetical case this cause would be removed, and we 
May conclude that the region of maximum.cold would be situ- 
ated nearly symmetrically with reference to our one great conti- 
nent, but inclined from the pole towards that continent, and from 
great Pacific Ocean situated on the opposite side of the pole. 
The probable longitude of its central poiut would be nearly that 
of the present western coast of Europe. This would bring the 
'sothermals in our hypothetical case, lying on the north of those 
already traced, into approximate. parallelism with the equator be- 
tween the eastern coast of Asia and the western coast of America. 
The distances between them (for such, at least, as should not be 
too far to the north) would necessarily be much the same as be- 
tween those of which the positions have been previously discus- 
tan isothermals of 32°, and the three succeeding it to the 
orth, 
_ The approximate positions of the winter isothermals on the 
South of that of 32°, and in the northern hemisphere, may 
easily inferred in like manner. It is not necessary here to discuss 
tem in detail. z se 
| Let us now take the July isothermals for the northern hemis- 
Phete. In Asia there would seem to be no reason why they 
ould differ materially iv the present case from the actually ex- 
Sting lines. West of the meridian of 60° E. the two lines of 
9 and 41°, delineated on Dove’s map, are manifestly affected 
by the Gulfstream, ‘The next to the south, that of 45°-5, to- 
ssther with the two succeeding lines, follow the inflection of the 
northern coast of Scandinavia, and must be considered as influ- 
Peas: 
