IN THE PRESSURE OF THE ATMOSPHERE. 485 
therefore evident that we must not attribute the annual peri- 
odical variation in the pressure of the atmosphere solely to the 
influence of the direction of the wind; and the figures in Table 
VIII., in which this influence is eliminated by calculation, actu- 
ally show how inconsiderable this influence is, as I proved 
sixteen years ago (Annalen, vol. xi. p. 583). It would likewise be 
perfectly useless to attach any weight to the short apices of the 
Europzan barometrical curves, after the entire pheenomenon has 
been ascertained to be a transition between the phenomena of 
sea-climate and those of continental climate; for that would be 
making the particular configuration of the coasts of Europe take 
part in this problem. It will be time for such local examinations 
when the general one is well-determined. The sudden bend of 
the North Asiatic curves (a concave bow between two more or 
less horizontal branches), in opposition to the uninterrupted curve 
of the localities in the district of the monsoons, will probably 
remain. We find North Asia suddenly drawn into a circle of 
phenomena to which it does not belong. It is a violent arousal 
from winter slumber, not a gradual and regular transition of re- 
lations mutually affecting each other, but the abrupt antitheses 
of the continental climate are without any intermediation. 
We are accustomed to compare the continental character of 
the climate of North America without hesitation with that of 
North Asia. This view is in my opinion erroneous, even in 
respect to temperature. North America and the arctic countries, 
covered with large surfaces of water, differ from Asia in their 
relations of temperature precisely by their not having that high 
summer temperature. We look in vain for the July temperature 
of Jakutzk, 16° to 17° R. at the Slave lake; in Ustjansk it is 
12°, in Boothia only 4°. The barometrical conditions in America 
are far more closely related to those of the sea-climate. If, for 
instance, we observe the form of the curve of Reikiavig in Ice- 
land, where the pressure from February to May increases, and 
then almost uninterruptedly falls until December, differing alto- 
gether from the EKuropzan and Asiatic barometrical curves, and 
compare with that (Table VI.) the stations of observation of the 
polar expeditions, of which however the observations at Winter 
island, Melville island, and Igloolik still require a considerable 
correction, on account of the constant temperature of the ships, 
we also find a corresponding maximum in May. The rarefaction 
during the summer months is certainly well-marked, even in this 
