CLIMATE.
The climatic divisions of the country.--Periodical rains.--Prevailing
winds of the continent.--Changes of temperature.--Consumption in warm
climates.--Cold, humid atmospheres.--What climate most desirable for the
consumptive.--The dry atmosphere of the interior.--Dry winds of the
interior.--Table of rain-fall of the whole country.
Until a comparatively recent date the climate of the continent was held,
by all of the more learned in matters of physical geography and climatic
law, to have but one general characteristic; but these conclusions have
been found to be utterly erroneous, and now it is known to be
susceptible of division into three great and entirely distinct areas,
each being highly marked, and leaving, on these various surfaces,
peculiar evidence of their existence.
Instead of an _oceanic_ climate prevailing over the entire continent, it
is found to have but very narrow limits along the Pacific coast of the
United States, being broken entirely from the interior by the elevated
mountain ranges, conforming to them throughout their entire extent, and
having a sweep from near the thirty-sixth parallel to Sitka and the
Aleutian Islands, away to the extreme northwest.
The second division embraces the great interior basin lying between the
ranges of one hundred and twenty degrees and ninety-two degrees west
longitudes, having a general trend from the southwest, at San Diego, to
Hudson's Bay in British America, in the northeast. This vast district is
paralleled by that of the interior climate and character of the
continent of Asia in its elevation, aridity, and great extent, and may
be known as the true continental or Asiatic climate of the United
States. It is on the edge of this district, and visibly under its
influence, that the State of Minnesota, for the most part, lies. But we
pass, for the present, to the brief consideration of the third grand
division, embracing the entire country east of a line drawn from near
Central Texas to the centre of Wisconsin, including the immediate region
surrounding all the great lakes. Here we have an association of elements
constituting a highly variable climate, which prevails over all its
surface at all seasons, with remarkable uniformity. The wide range in
both vegetable and animal life over this area is one of its chief
distinguishing characteristics, partaking of the semi-tropical on the
one hand, with a low winter temperature on the other, but traversing
neither range so far as to prove directly destructive in its effects.
All over this eastern area are scattered lakes and rivers, with an
ocean boundary line, and uniform forest ranges with a great variety of
deciduous trees known to the temperate and sub-tropical latitudes; and
it is quite remarkable to note that some of the latter forms extend in
their acclimation to near the northern boundary lines of the Union,
while the pine, walnut, and chestnut may be found at or near the extreme
southern limits.
In all of these three grand divisions of climate, however, exceptional
localities exist where there is a marked nonconformity to the prevailing
characteristics. The peninsula of Florida is such an exception, owing to
its peculiar location, and the great humidity of its atmosphere during a
considerable fraction of the year. Here we have a fully developed season
of periodical rains, beginning usually in June and ending in the latter
part of September. The winter is the dry season, being contrary to the
general rule applying to tropical and sub-tropical areas, and forms,
with the mild temperature, the principal ground for the reputation which
that State has as a resort for special classes of invalids.[B]
The sudden and extreme variations of temperature in this eastern
climatic tract, whether from local disturbing causes, as is not
unfrequently the case, or otherwise, are usually accompanied by cold
draughts of air, chilling and generating all manner of ills, of which
rheumatism and consumption are the separate and highest types.
While it is generally understood that the prevailing winds of the whole
continent embraced within the limits of the United States are uniformly
from the west, still, over this eastern division, counter-winds of a
lower character disturb, modify, and elevate the course of this great
westerly current, giving rise to the exceeding variability of the
surface winds, which, as is well known, may blow within the brief space
of twenty-four hours from all directions of the compass, at almost any
time and point whatsoever.
Changes of temperature, while essential in some circumstances to health,
may be, if of a certain specific character, infinitely damaging, and
such are the cold humid winds from the northeast with easterly
inclinations. These are the dreadful scourges of all the Atlantic slope
above the Carolinas, and there is scarce any portion east of the
Mississippi Valley free from their occasional visitation. In the extreme
southern limits, along the Gulf, and on the Peninsular State, the
poison, so to speak, of this wind, is so far modified by the greater
temperature of these localities as measurably to disarm it of danger;
yet, even in those latitudes, it is to be (during and after a prolonged
storm) avoided by all, and especially weak and enfeebled constitutions.
The cases of consumption found in these warmer climates have been cited
as disproving the heretofore accepted theory that this disease was
limited in range to the middle and eastern portion of the Union; and it
has been further assumed that the liability to its attack was as great
there as at any point further north.
These conclusions have little foundation in fact, as is well known by
all who have taken pains to investigate the question with that
thoroughness which the subject demands. The catalogue of ills belonging
to all warm climates is not only long enough, but likewise sufficiently
dreadful, without adding to it that scourge, which is the child of the
northeast winds, with its home in the changeful temperature along the
upper Atlantic coast. It is quite true that cases occur in even tropical
districts, but they are the stray offspring of some unusual departure of
the cold and humid northerly currents. It must not, however, be taken as
a sequence of this proposition that any and all warm countries would
prove a sovereign balm and remedy; but, that there are a few localities
of this condition in temperature, where patients of the class under
consideration may reside with positive advantage, and not unfrequent
restoration to health follow, we both believe and know.
But there is so great a liability to contract some of the many fatal
febrile, and other diseases of hot countries, together with their
usually excessive humid character and greatly enervating effects,
especially on those who have been born and reared in cooler and higher
latitudes, that it comes to be a serious question for consideration
whether the chances of remedy hoped for in a residence at such places is
not more to be dreaded than the disease itself.
In what direction, then, can the invalid turn with any immediate or
ultimate hope of either relief or a permanent cure? We answer, that any
place where a dry, equable climate can be found, all other things being
equal, will give the desired relief and probable cure, if resorted to in
season, and if certain hygienic regulations be carefully and
persistently observed. The next question is, have we a climate answering
this important requirement, and, at the same time, outside of the range
of epidemics and fatal fevers; easily accessible, and affording, when
reached, the necessary comforts and aids incidental to a restoration? To
this we have an affirmative reply to give, coupled with some
modifications, and point to the Central climatic division of the
continent as possessing, in its dry elastic atmosphere and generally
equable temperature, the requisite desideratum.
Minnesota lies within this division, and, while upon the outer edge, is
still markedly under the influence of the prevailing climate which
distinguishes the whole of this middle area. Other sections within its
limits there may be, and, indeed, doubtless are, just as favorable, if
not more so, than is that of Minnesota, but they are lacking either in
facilities for reaching them, or in the needed comforts, and perhaps in
the commonest necessities which are absolute in all cases,--a wholesome
diet being one of the great essentials to recuperation.
Minnesota affords, of course, all of these aids in large abundance, and
is likewise quite easy of access, thus answering, in these particulars
at least, the ends desired.
It may now be well to examine the chief characteristics belonging to
this central climatic division, on the northeastern edge of which lies
the State under special consideration. We have already observed that the
prevailing and prominent winds of the continent blow uniformly from the
Pacific toward the Atlantic coast, having a slight northerly tendency.
It is important that this fact be kept in mind. This wind is constantly
sweeping across the North Pacific Ocean, by which it is tempered and
ladened with a vast amount of moisture, which is borne to the shores of
the continent, and, but for the elevated mountain ranges along the whole
of that coast, would be quite evenly distributed over the interior,
giving to all of the western and central area such an abundance of
fertilizing rains as the western half of the continent of Europe now
possesses, and to which this would then be in climate almost an exact
counterpart. But instead we have only a slender breadth of territory
answering to the oceanic climate of Western Europe, embracing that which
lies between the Pacific shores and the Sierra and Rocky Mountain
ranges. Within this belt is precipitated nearly all of the moisture
contained in the atmosphere. The warm, humid westerly winds, driven
against the lofty and cool mountain sides, have their moisture suddenly
and rapidly condensed, and the rain-fall on their western slope is found
by measurement to be prodigious, reaching as high as sixty-five cubic
inches for the year, being equal in quantity to that falling in many
tropical districts, and greatly exceeding that of any other portion of
the United States. These mountains have a determining influence on the
climate, both of the coast and of that in the interior. They act on the
clouds as they sweep against and over them, like a comb, extracting all
possible moisture, leaving a cool, elastic, and arid continental
atmosphere for this central area under present review. The effect is at
once pronounced and everywhere visible. Less than two degrees of
longitude _east_ of these mountain ranges there is but about (taking the
whole line from the thirty-fifth parallel to the northern boundary) an
average fall of seven and a half cubic inches of rain, a difference of
over fifty-five cubic inches within the year, in districts separated by
less than one hundred miles in a straight line from each other. The
consequence is, that, while in one there is a luxuriant growth in all
kinds of vegetation, in the other barren plains (destitute of all except
the lowest forms of vegetable life) exist, with a gradual but slow
return, as the eastern course of the winds are followed, to that normal
condition which prevails in districts where an abundant supply of
moisture is furnished. This is not fully found till the western limit of
the third climatic division is reached, where again we see on all hands
a general distribution of rivers and forests over the whole of this
area, with copious rains at all seasons, and humid and cool conditions
of the atmosphere, following each other in rapid alternations; producing
what we have seen fit to call the Variable climatic district, embracing
the whole eastern half of the continent.
The extreme high temperature of the interior division equals that of
points lying a dozen degrees south in other longitudes, and the
desiccated winds from the west, as they blow over this parched and
heated surface, have their aridity rather than their humidity increased,
as would be the case in other circumstances; and not till they reach
within perhaps five hundred miles of the eastern boundary of this
continental division do they increase in humidity, as indicated by the
rain-fall, which rises in quantity from the low minimum of seven and a
half cubic inches per annum in the "great basin," and fifteen on the
"great plains," to about twenty in Dakota territory and twenty-five in
Minnesota, the eastern limit of this continental climate.
The effect of these dry winds on the humidity of the atmosphere in
Minnesota is unquestioned and demonstrable by the records kept of the
various governmental posts over the whole country. In contrast, the
amount of rain falling annually in this State is shown by these
statistics to be much below that of any lying east of the Mississippi,
in the variable-climatic district; and, indeed, below that of every
other in the entire Union, excepting Nebraska, which averages about the
same amount of rain-fall, though without the same amount of dryness and
elasticity, which are such notable features in the atmosphere of the
former State.
The mean annual amount of rain falling in New England is about
forty-three inches, nearly double that of Minnesota, exhibiting the vast
difference in the humidity of the two localities, and this, in
connection with the cold easterly winds before referred to as prevailing
there at intervals, together with the severe changes (and which, it
should not be forgotten, add to the quantity of moisture), may be
ascribed the primal cause of all pulmonic diseases.
It should not be understood, however, that the _quantity_ of moisture
precipitated in any given district determines of itself the prevalence
or non-prevalence of phthisic complaints; not at all, for we see in
Florida the rain-fall is very great, and as much exceeds that of New
England as the latter does that of Minnesota, and consumption has no
home on the peninsula of Florida. Why it has not, inheres in this fact,
that the climate does not, or rarely, experience any of those violent
and chilling changes of temperature that are almost constantly going on,
especially in the fall, winter, and spring months, and which do the
fatal work of death. But, some one says, the northeast winds reach
Florida, and why do not the inhabitants suffer from it? For the reason
that they are greatly changed in character, becoming mild and only
pleasantly cool in temperature, offering no shock as a rule; and really
the northeast trades, which almost daily blow, are the invigorating and
healthful winds, sweeping away the miasma of the hot season, cooling the
atmosphere, and preserving equability throughout the year. Then there
are other matters; the drainage qualities of the soil, which is so great
on that peninsula; then, too, is the distribution of the falling rain,
whether it is filtered slowly through all the year, keeping things
constantly drowned out, or in a state of flabbiness, or whether it is
mainly confined to a single season or an inconsiderable fraction of the
whole year, as in Florida. These become important inquiries, as all have
a bearing on the question of the _healthfulness_ of climates.
We have stated the rain-fall to be less in Minnesota than in any other
State in the entire Union, with one exception; and while this is true,
it is still great enough for all agricultural uses, coming chiefly in
the summer months, at a time when the crops are growing; and, by the
middle of September, as a rule, the quantity has fallen off to a very
low mean, accompanied by that elastic, invigorating atmosphere for which
the State is so justly famed. This season of charming weather continues,
with little interruption, only accompanied by a gradual diminishing
scale of thermometric registration, up to the advent of winter, and even
then the moisture falling in snow is less than is generally supposed or
believed.
Since these matters are of vital character in determining the salubrity
of the climate of this State, we append the following table, both for
the purpose of comparison with other places and definiteness concerning
this.
This table gives a sweep of country from ocean to ocean, and exhibits
the rain-fall of the three climatic divisions very faithfully. The great
quantity precipitated at Astoria, in Oregon, is observed, where the
OCEANIC climate prevails, with the mountain barriers limiting its extent
inland; while, at Port Laramie, in Wyoming Territory, is an average
representation of the whole interior district possessing the dry and
elastic CONTINENTAL climate, in which lies the State of Minnesota. The
other portions of the table give a more extended view of the VARIABLE
climate, covering the eastern area as previously defined.
_Average Annual Fall of Water (rain and snow, given in inches) for a
Series of Years, as ascertained from Official Sources_.
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PLACES. | WINTER.| SPRING.| SUMMER.| AUTUMN.| YEAR.
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Fort Snelling, Minn.| 1.92 | 6.61 | 10.92 | 5.98 | 25.43
Fort Ridgely, " | 4.11 | 7.29 | 9.29 | 4.83 | 25.52
Astoria, Oregon | --- | --- | --- | --- | 65.00
Fort Laramie, Wy. | 1.63 | 8.69 | 5.70 | 3.96 | 19.98
Fort Crawford, Wis. | 4.00 | 7.63 | 11.87 | 7.90 | 31.40
Fort Gratiot, Mich. | 5.75 | 8.02 | 9.99 | 8.86 | 32.62
New Harmony, Ind. | 12.29 | 10.51 | 12.79 | 7.26 | 42.85
Cincinnati, Ohio | 11.15 | 12.14 | 13.70 | 9.90 | 46.89
St. Louis, Missouri | 6.94 | 12.30 | 14.14 | 8.94 | 42.32
Chicago, Illinois | --- | --- | --- | --- | ---
Philadelphia, Penn. | 10.76 | 9.81 | 11.93 | 9.84 | 42.34
Lambertville, N.J. | 9.67 | 11.25 | 12.15 | 11.59 | 44.09
Fredonia, New York | 6.82 | 7.24 | 10.45 | 12.04 | 36.55
Utica, " " | 8.72 | 9.26 | 12.83 | 9.76 | 40.57
Albany, " " | 8.30 | 9.79 | 12.31 | 10.27 | 40.67
Brooklyn, " " | 9.83 | 11.75 | 11.43 | 10.35 | 43.36
Providence, R.I. | 9.44 | 10.45 | 9.66 | 10.50 | 40.05
New Bedford, Mass. | 10.42 | 10.67 | 9.18 | 10.76 | 41.03
Worcester, " | 11.85 | 10.89 | 10.71 | 13.51 | 46.96
Cambridge, " | 9.89 | 10.85 | 11.17 | 12.57 | 44.48
Hanover, N.H. | 9.10 | 9.90 | 11.40 | 10.50 | 41.00
Portland, Maine | 10.93 | 12.11 | 10.28 | 11.93 | 45.25
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The fall of snow has been in this statement reduced to a water basis,
allowing, as is the usual custom, ten inches of snow for one of water.
This calculation is not entirely reliable for all points; as, at the
extreme southern snow-line, a less, while a larger amount is required
for a more northerly district--say about eleven inches to make one of
water in Minnesota. This would give a depth of about two and a half
feet (snow) over the surface of the State for the entire winter months,
while in Central New York--to which in mean annual temperature Minnesota
parallels--the depth of all water falling, for the same season, would
(in snow) amount to full five feet, or double that of the State under
consideration.
FOOTNOTES:
[B] For further particulars of Florida climate, see _A Winter in
Florida_, by the author of this volume, published by Messrs. Wood &
Holbrook.