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those, however, who can consult such charts it is possible, so 
to speak, to take their stand at a higher point of view and 
survey the conditions prevailing, say over Europe, on any 
given day. 
If the amount of change in the pressure or of rise and fall of 
the barometer during the preceding night be plotted every 
morning on such a chart, it is found that the path of the 
system for the day does not lie directly towards the region 
where the greatest fall has occurred during the night, but is 
regulated to a certain extent by the direction of the line drawn 
from the point of greatest fall to that of greatest rise. 
Another theory of storm motion, strongly held by those who 
attribute all our storms to condensation of vapour, is that the 
track of the depression is always directed towards the region 
where the air is dampest. This principle, like that just noticed, 
can hardly be turned to account in this country for our own 
practical benefit, inasmuch as the whole of these islands appear 
to be almost equally damp, owing to the proximity of most of 
our telegraphic reporting stations to the sea. 
Other suggestions have been made in various quarters, with 
the view of throwing light on this very important subject ; but 
we cannot say that the results have met with general acceptance, 
and the matter urgently demands further study. 
I must now come to the final portion of my theme — the 
Death of a Storm ; and on this subject, unfortunately, I have 
very little to say. As we have not been able to produce evi- 
dence of the birth of a storm, so have we never been lucky 
enough to find any one who was in at the death. In fact, some 
French meteorologists have hazarded the statement that storms 
can travel all round the world until at last they travel off it. 
Storms have been traced from the Pacific coast of North 
America across the Atlantic ; but these instances are necessarily 
rare, and, as far as European experience goes, no storm arriving 
from the Atlantic ever travels far into Russia. This fact is, of 
course, very much in favour of the condensation theory of storm 
generation, which has already been noticed. The advocates of 
this view plead very plausibly that, as the moisture in the air 
is the food of the storm, so, where that moisture is deficient, 
the storm dies of starvation. 
We may, however, point out to them that eddies in a river 
and dust whirls at street corners waste and wane without any 
assistance from vapour condensation. 
In conclusion, though it is a humiliating confession for us to 
make, meteorologists are as yet entirely in the dark as to the 
reasons why one depression fills up while another becomes 
deeper. As I have already stated, no meteorologist is able to 
give a straightforward answer to the simple question, What 
causes the barometer to rise or fall ? 
