States in less than forty-eight hours, appeared on the 26th 
in full force in Northern Florida, but not until some eight 
or teh hours after it had set the atmosphere all around it 
(as far north as Boston) in cyclonic motion, and had 
caused the storm-cloud to spread itself over the entire 
region of the United States on the eastern slopes of the 
Alleghanies, and as far westward as Knoxville, Tennessee. 
It is no uncommon thing, as Redfield, Espy, Henry, 
Loomis, and others, long ago showed, for an area of de- 
pression on the upper lakes to make itself simultaneously 
felt as far south as the Gulf of Mexico, and as far east 
as New England. 
If it fell within the scope of the design of this paper 
to consider the final cause of storms, it~ would be 
easy to show that, unless the law of storms ordained a 
large area, and a far extended path for the meteor, in 
some degree commensurate with the area of our immense 
continent, the meteor could not fulfil its office in the 
terrestrial economy—an office which, apparently, imposes 
upon it the task of gathering to its centre, through the 
agency of its intro-moving winds, the idle and inappre- 
ciable moisture scattered over the surface of the earth, 
condensing it into rain and snow, and diffusing it in these 
forms over immense districts of country. 
. It is of incalculable importance to observe, and care- 
_ fully digest the fact, that when a storm-centre or area of 
i low barometer is once formed, it is the nucleus for a vast 
: 
: 
i 
aggregation and marshalling of meteoric forces. No 
matter how small at first, under favourable atmospheric 
conditions, the courant ascendant is formed, condensation 
aloft sets in, and the precipitation only serves to add 
“fuel to the flame” of the cyclonic engine. This process 
widens in geographical area, and after a few hours have 
elapsed, the storm may so develop as to cover a continent 
_ with its portentous canopy of cloud, while simultaneously 
strewing an ocean with wrecks, and throwing out in the 
upper sky, more than a thousand miles in its front, the 
fine filaments of the premonitory cirrus and cirronus. 
In close connection with the size and magnitude of 
cyclones must be considered the distance over which they 
pass from their initial point. Much has been said on this 
part of our subject, and not a few writers have accepted 
the doctrine of Admiral Fitzroy, that they progress over 
but comparatively short distances. For such a view, 
however, it is impossible to find, either in the hature or 
physical office of the cyclone, any support whatéver. The 
storm once engendered, ho matter in what fart of the 
world, thay be stationary or progressive. There are well- 
alithehticdted instances of alitiost stationary cyclones 
and Aliiiost stationary typhoons, of which latter will 
‘be reniembered the famous gale of the ship Charles 
‘Heddle—an (ndiaman, carried round and round the storm- 
- centre for five days—which progressed not more than 90 
miles a day. Indeed we may, as has been said, regard every 
wet-imonSoon region as a stationary and semi-perennial cy- 
clone. Such a meteor has been shown to resemble an eddy 
moving in the current of a rapid river. The latter may 
be large or small, while it does not determine, but is 
determined by, the course of the on-flowing stream, It 
is true the centre of an eddy or water-hollow may soon 
be filled up and the whirl disappear ; but it is because 
the depression is not maintained. If the depression 
could be maintained, it is easy tosee that the eddy 
would continue, arid pursue its way, as long as the current 
in which it is embodied continues to flow ; it might be 
through the length of an Amazon or a Mississippi River. 
In the case of a cyclonic eddy or whirl, we know the 
atmospheric depression is maittained as long as the 
centre moves ina region sufficiently supplied with aqueous 
vapour to feed it. It is a physical impossibility, as has 
been Often showwii, that any storm, however vast or how- 
evét Violent, can prolong its advance or sustain its fury 
over a dry and desiccated surface. Thé most extended 
typhoons of the East, upém enteting the dry and rainless 
continental regions, dwindle into the well-known and 
diminutive dust-whirlwind, such as Sir S. W. Baker 
describes as witnessed in Nubia, and as here illustrated, 
from the admirable pages of Mr. Buchan. The Sahara 
is amore formidable barrier to the passage of a storm 
than the majestic mountain wall of the Alps, and the 
simoom is, notwithstanding the stories of travellers and 
the legend of swallowing up the army of Cambys2s on 
the African desert, a wasted and worn out cyclone. In 
his “ Desert World,” Mangin, compiling the more accurate 
observations of the phenomenon, says: “It never prevails 
Over any considerable area, and beyond its limits the 
atmosphere remains serene and calin; the phenomenon 
is of brief duration, the atmospheric equilibrium is 
speedily restored ; the heavens recover their serenity ; 
the atmosphere grows clear, and the sand-columns, falling 
in upon themselves, form a number of little hills or cones, 
apparently constructed with great care, like those mimic 
edifices of sand made by children in their pastime.” 
The same writer also mentions a severe simoom which 
was “ over in a couple of hours.” 
Embedded in the great aérial currents, however, ‘and 
supplied with abundance of moisture, there is nothing 
to arrest either the rotatory or progressive movements of 
the storm. Like the drift-bottles cast upon the current 
of the ocean, and found after months to have been 
carried thousands of miles, from the equatorial to the 
polar parallels, there is every reason to suppose the 
tropic-cradled gale, and the minor storms also, are borne 
in the great atmospheric currents through quite as great 
distances. There is an authentic and well-attested account 
of a Japanese junk, lost or deserted off Osaka, drifting 
through the immense arc of the Kuro Siwo’s recurvation, 
and encountered (in latitude 37°, by the brig Forrester, 
March 24, 1815) off the coast of California. That tiny 
craft must have followed in the bands of westerly winds 
and warm waters for seventeen months, Why, upon 
theoretical grounds, should we reject the hypothesis which 
represents the movement of storm-areas as prolonged for 
many thousands of leagues, or indeed that which repre- 
sents them perpetually in motion around given centres of 
cyclonic or anti-cyclonic areas, keeping pace with the 
great winds in their eternal circuit ? 
As a striking corroboration of all this we find—what 
might have been assumed on theoretical grounds—that 
the logs and special observations of the Cunard steamships 
show that a vessel bound from Liverpool westward en- 
counters frequent advancing areas of low pressure, 
indicating a number of rapidly succeeding barometric 
hollows or depressions, “ each with its own cyclonic wind- 
system, moving across the Atlantic as eddies chasing 
each other down a river-current.” > 
The word cycfone has frequently, but incorrectly, been 
used as significant of an enormous or very violent meteor, 
as if its applicatioh was to be confined to the devastating 
hurricane of the West Indies or thé terrific typhoon of 
the Chinaseas. It simply means a Storm which acts in 
a circular direction, and whose winds converge by radials 
or sinuous Spirals, toward a centre, Moving in our hemi- 
sphere in the opposite direction to that of the hands of a 
clock, and in the Southern Hemisphere in a contrary 
direction. Taking this as the definition of a cycloné, 
it seems clear, from observation alone, that all storms are 
to be regarded as cyclonic. Volumes have been written 
to prove that this is not the case. But we have only to 
examine a few series of weather-maps from week to week 
to see that, wherever you have an area of low barometer, 
into its central hollowthe exterior atmosphere from all sides 
will pour, and that in so doing a rotatory spiral or vorticose 
storm is generated. The tornado, the simooms, the dust- 
whirlwind, the fire-storm, even the slowand sluggish storm 
which moves on our western plains as the labouring wheel of 
the steamship buried in a heavy sea, all attest thata Body 
cannot move on the earth’’ siface ih 4 ema Tie. Tt 
