the earth has ever been a matter of the greatest interest to the
students of geography. It was the incentive that led the daring
navigators of old to undertake the perilous voyages that in these days
read like romances; and in the light of the more perfect knowledge we
now have of the hidden dangers to which they were exposed, we may pass
by their shortcomings in the admiration we must feel for their heroism
and endurance. To these men we owe our first conception of the probable
distribution of the areas of land and water, but the lines they gave us
were only approximate; and had not scientific effort followed in their
tracks we may reasonably believe the progress of civilization would
have been retarded by generations. True it is, also, that even to-day
we have not that precise knowledge that is requisite for the safety of
quick navigation, nor to calculate the possibility of the future
improvement of undeveloped regions. The commerce of the world in coming
years will demand the accuracy in the location of distant regions as
great as we now have in civilized centres, for time will be too
precious to lose a day of it in the precautions that the navigator must
now follow in approaching undeveloped coasts. That these truths have
guided those who seek to do their share for the future in the labor of
the present, we have ample evidence in the activity of all civilized
governments during the last century. It is a source of shame and
infinite regret that our own government has done so little in this vast
field: that the intelligence of our people has not been awakened to put
forth their energy in so good a cause, that would eventually increase
their own prosperity. But we have not been altogether inactive and
complaint must be in the quantity, not the quality of our labors. The
establishment of "definite locations," for the control of sections and
regions, is the first step in eliminating errors that have been
committed and in providing greater accuracy in the future. At a recent
meeting of the Society we had a paper presented on this subject, from
which we can judge of the good work that has been done by our navy in
these determinations, and gain an insight of the similar labor that has
been prosecuted by other nations. The bands of electric cables that
girdle the earth, afford the most approved means of ascertaining the
longitudes of these positions; and if we but study a cable chart, it
will be found the work yet to be accomplished before the facilities the
cables now afford are exhausted, is not inconsiderable. We hope,
therefore, this good work may be continued, and that surveying and
charting the regions thus approached, will shortly follow. There is
much labor of this character still required on our own continent, and
we will be delinquent in our duty as a progressive people if we do not
follow the good beginning already made to its legitimate conclusion.
The duties of government are manifold, and for the benefit of those
governed must include legislation that will make manifest the natural
resources of the State. The geographic development and political
advancement of our own country in the century of our national
existence, is a marked instance of the wisdom of preparing for the
future by such acts as legitimately fall within the province of
legislation.
The new nation began her existence under extraordinary circumstances.
With only an experimental form of government, she was to develop a vast
region of unknown resources; but happily imbued with the belief that
"knowledge is power," it was not long before systematic efforts were
put forth to learn the wealth we had and how it might be utilized. The
congress of the confederation provided the first act in 1785, for the
organization of the land surveys and land parcelling system, that title
to the unoccupied territories in the west might be securely vested in
the individual. We have record of the stimulus this act gave to the
settlement of a large territory, and raised the demand for surveys in
the still further west, developing the geography of a vast region that
has since become the home of millions of people. The original act was
amended as early as 1796, and since then has frequently been added to
in the effort to meet the new conditions evolved in the rapid
development of the country. Other great regions were explored by the
army, sometimes under special acts, until finally we had learned with
some degree of reliability, the general adaptability of our whole
territory. The discovery of the great mineral wealth of the west, and
the improved means of communication afforded by the construction of
continental railways, however, imposed new conditions and it was found
more detailed information would be necessary to meet the demands of the
increasing population. We thus reached another stage where expeditions
equipped for scientific investigation were organized, and through their
labors brought us knowledge of still greater value; and to-day we see
these merged into one body in the geological survey, whose special duty
is the scientific exploration and study of our great territory.
While this had been passing in the interior, bringing life to
unoccupied regions, the districts on the coast that had long been
settled, were also struggling with new problems. The material progress
of the civilized world, and the pressure from the regions behind them
that had been recently peopled, demanded greater commercial facilities.
Early in the century, almost coincident with the establishment of the
land surveys, provision had been made for the survey of the coasts, and
although through various causes it was not vigorously prosecuted until
a third of the century had passed, when the time came for its economic
use in meeting the new conditions imposed by the general progress of
the nation, the knowledge had been gained that was essential to advance
and develop the great interests affected. The improvements required,
however, could only be secured through active exertion, the actual work
of man; but so pressing has been the want and so persistent has been
the labor, that should we chart the results it would be a surprise to
those who believe the "local geography" has not been changed.
The demands upon the older communities arising from the increase in
commercial and industrial enterprise, have caused them too, to feel the
want of more detailed information of their surroundings, and they have,
in consequence, undertaken more precise surveys of their territories,
generally availing themselves of the assistance offered by the general
government. This work will doubtless extend in time to all the States,
and be followed, when its value has been made manifest, by the detailed
surveys of precision that have been found necessary as economic
measures in the civilized States of the old world.
It is rarely we can foresee the full results of great national
enterprises; the special object that calls forth the exertion may be
readily comprehended, but the new conditions evolved from success, and
sometimes from only the partial accomplishment of the original design,
may be factors in governing the future beyond our power to surmise.
The work of improving the navigation of the Mississippi River, is an
instance of this character so marked, and apparently destined to extend
its influence through so many generations, that a brief record of the
change it has effected in geographic environment will not be without
interest, and, perchance, not without value.
The area drained by the Mississippi river and tributaries, is forty-one
per cent. of the area of the United States, exclusive of Alaska; and by
the census of 1880 the population of this great district was
forty-three per cent. of the whole Union. It seems probable that a
large proportion of this population is directly interested in the river
system, and if we add to it the number of those who are indirectly
benefited, we should doubtless find a majority of our people more or
less dependent upon its maintenance. It is only to the alluvial valley,
however, the great strip from Cairo to the Gulf, that I wish
particularly to call your attention this evening. This is really the
great highway for traffic; the cause of the great work that has been
prosecuted; and the scene of the geographic development that will mark
an epoch in the history of the river.
Ten years ago the importance of the improvement of this water-way was
so forcibly impressed upon Congress, that an act was passed organizing
a "Mississippi River Commission," to make an exhaustive study of the
whole subject and submit plans for the improvement of the river and to
prevent the destructive floods that are of almost annual occurrence. Or
in the language of the act: "It shall be the duty of said Commission to
take into consideration and mature such plan or plans, and estimates,
as will correct, permanently locate, and deepen the channel and protect
the banks of the Mississippi river; improve and give safety and ease to
the navigation thereof; prevent destructive floods; promote and
facilitate commerce, trade, and the postal service."
Large sums of money had already been expended by the general government
in local improvements, but no consistent plan had been developed that
would be an acceptable guide in conducting operations along the whole
river, when this act went into effect. It is not necessary to refer
here to the various systems that were presented to the Commission for
consideration; nor to enter upon the details of the plan finally
adopted; our record being more the effects and primary causes, than the
intermediary processes through which the results have been produced.
The general plan followed by the Commission has been the construction
of works in the bed of the river, to form new banks where a contraction
of the river bed has been deemed necessary; and the erection of levees,
with grading, revetment, and other protection of the banks, in
localities where the natural banks seem particularly liable to give way
under the pressure of a great flood. The object of such works being to
control the river by confining the low water channels in fixed lines,
causing the recurrence of the scour in low water stages in the same
channel in successive low waters; and preventing the diversion of the
stream into new channels during high water stages by overflow of the
banks. A diversion of the stream would leave the works in the bed of
the river below of no greater value than as monuments to the energy and
skill displayed in the details of their construction, and preclude the
ultimate benefit that may be derived from these works in permanently
lowering the bed of the river. The probability of such diversion of the
water, however, seems to have been reduced to a minimum, through the
conservative action of the Commission in coöperating with the States
having jurisdiction over the alluvial bottoms, in reorganizing their
levee systems and thus securing the greatest control over the volume of
water brought down in the flood seasons, that is possible by the
construction of well planned and substantially built levees. It having
been demonstrated that the levees subserve a double purpose, that they
are essential in the general plan to improve the navigation of the
river adopted by the Commission, and are likewise needed to render the
bottom lands habitable, it is not surprising that we find the State
authorities and the Commission jointly engaged in their construction.
It has thus been brought about that the effort to improve the
navigation of the river for the general welfare, has resulted in such
great changes in the geography of the locality, that a large district
has been reclaimed for agricultural purposes. The alluvial valley of
the Mississippi river has an area of thirty thousand square miles, and
is naturally divided into four great basins that have been designated
the St. Francis, Yazoo, Tensas and Atchafalaya. Two of these basins are
now fairly protected from the overflows of the Mississippi, by the
levees that have been constructed, or repaired, incidental to the work
of the Commission, viz: the Yazoo basin extending from below Memphis to
the mouth of the Yazoo river; and the Tensas basin from the high land
south of the Arkansas river to the mouth of the Red river; and the
Atchafalaya basin, from the Red river to the gulf, has been protected
on the Mississippi fronts. These three basins have an aggregate area of
nearly twenty thousand square miles that is now reasonably secure from
inundation. Measures have also been instituted by the State authorities
looking to the reclamation of the St. Francis basin; and the work is
half accomplished on the White river section.
Nearly the whole of this valley was under protection thirty years ago,
but the disasters of the late civil war, and subsequent inability of
the people to repair the damaged levees, resulted in the practical
abandonment of many sections, and it was not until about ten or twelve
years ago that the protective works again presented an appearance of
continuity. The supposed security, however, was of short duration, as
the great floods of 1882 overtopped the works in more than one hundred
and forty places, causing such widespread destruction that cultivation
of the soil was rendered impossible over large districts. The floods of
succeeding years but added to the misfortunes of the valley, and land
values became so depreciated that sales were impracticable, taxes could
not be collected, and there was a general feeling that square miles of
fertile land must be given over to the destructive agencies of the
great river that had made it.
It was while suffering under this distressing situation that the work
of the Mississippi River Commission was brought forward as a possible
means of salvation. With a recuperative power that seems almost
marvelous, the people have contributed of their labor and their means,
until now this great area of nearly twenty thousand square miles has
been once more reclaimed, and seems to have entered upon an era of
prosperity that will eclipse the prophecies of even the most sanguine.
It is believed that the levees that have now been constructed will
prove reasonably secure. They have been built for a double purpose; and
the proportion of the expense incurred by the general government, about
one-third, under the direction of the Commission, has insured a
supervision and inspection by competent engineers such as was not
exercised in the earlier history of such works on the river.
We cannot foretell the developments that will follow the improvement of
this water way and the reclamation of the alluvial bottoms on an
enduring basis. That the works erected by the Commission will maintain
an increased depth of water at the low stages of the river, seems to be
demonstrated, as during the low water of November last a depth of nine
feet was found on the Lake Providence and Plum Point bars, an increase
of thirty-three and forty-four per cent. respectively. When the depths
on the other bars have been increased in like proportion the free
navigation of the river will be assured, and we may point to the result
as one of the greatest engineering achievements of modern times.
The increased value of the land adjacent to the river redeemed from
waste, more than doubled on the average, and in many instances
quadrupled; the replenishing of the state and county treasuries by the
collection of taxes on land that was before unremunerative; and the
building of railroads through sections where it had been impracticable
to maintain them before in consequence of their liability to
destruction by the periodic floods; are marked evidences of the
material prosperity that has already followed the great work. During
the last four years, forty thousand settlers have taken up lands in the
Yazoo basin alone, and it was estimated that in the fall of 1889 twenty
thousand more would seek homes in the same district. These settlers
have been mostly negroes from the worn out high lands to the eastward.
If the change in their environment proves beneficial to the individual
we may expect an increased migration, that may in turn be an aid in
solving the political problem involved in the citizenship of the negro.
The settlement of these bottom lands will also influence the prosperity
of many commercial centers, as trade statistics indicate the general
abandonment of the plantations that followed the great floods of 1882,
caused a marked diminution in the shipments by the lower river, as well
as in the receipts from that section; and that the partial reclamation
of the lands and restoration of agricultural pursuits has already
influenced the receipt and distribution of commercial products.
The project to reclaim by irrigation large districts of the arid region
of the west, if successfully accomplished, may also exert an influence
in the political and commercial relations of the future that cannot now
be foretold. Two-fifths of the territory of the United States has been
classed as arid; not in the sense that there is no water, for the
greatest rivers on the continent have their sources almost in the midst
of the region; but rather that the water is not available for enriching
the ground. The rainfall is generally not in the season when the crops
would require it, or is too small and uncertain for the husbandman to
depend upon it. The whole region is not of this character; many
districts are susceptible of the highest cultivation as nature has left
them, and others have been redeemed by the application of the water
supply through the simpler devices customary in irrigated countries;
until now nearly all the districts have been occupied that are
susceptible of agricultural pursuits, either in the natural state or by
irrigation, unless water is secured by means generally beyond the reach
of the individual or combination of individuals who may use it. And
yet, it is believed there are millions of acres of rich land that may
be redeemed and converted to the support of a large population, by the
application of capital in the construction of works of irrigation. The
progress of the surveys of the region, therefore, that have been
instituted by the general government, are watched with absorbing
interest. The districts susceptible of such extensive improvement are
only approximately known, and as it is only through these surveys their
availability will be made manifest, the importance of the work can
hardly be overestimated. The prosperity of several states will be
largely influenced by the success of operations of this kind within
their borders, and in turn their greater development and increased
wealth, must react upon the older communities and benefit them, on the
principle that the healthful growth of a single member is strength to
all.
The science of geography, as taught in the present day, is more
comprehensive than the brief descriptions and delineations of the areas
of land and water that satisfied the early explorers. The great strides
that have been made in scientific research during the past century have
opened new fields, and men are no longer content to picture that only
which they can see. The varied features of the earth's surface,
transformations now in progress and those which may be deduced from the
facts we can observe, have led to many theories of the construction of
the earth, ancient forms upon the surface and possibilities, if not
probabilities, in the future. To ascertain the form of the earth has
alone been the cause of heroic labor, and yet we have hardly passed the
point that we can give it in probable terms with the general
dimensions. Observations warrant the assumption that, discarding the
accidents of nature--even the highest mountains--the sphere is far from
being perfect. That it is flattened at the poles is now accepted as the
true condition, but we have reason to believe, too, that this is not
the only departure from the perfect sphere. The more thorough the
research and precise the observations, the more certain does it appear
that the crust has a form as though there had been great waves of
matter that had been solidified. To locate the depressions of these
great waves and measure their depths, to point to the crests and
measure their extent, is a problem for the future to solve. Their study
is claimed to be within the legitimate sphere of geography; and not
until they have been satisfactorily answered can we assert the
geographer is even approaching the end of the facts his science has yet
to utilize.
In pre-historic geography we have had two papers presented to the
Society during the past year, relating to the orographic features of
the earth's surface in times past compared with the localities as we
may see them to-day. In the first instance the comparison is evolved
from an effort to trace the origin and growth of the rivers of
Pennsylvania; and the second, in a description of the famed district
around Asheville, North Carolina. These have a substantial interest to
us, treating as they do of localities so well known; and they
illustrate, too, the resources of induction in bringing to our view the
probable wonders of ancient geographic forms.
The constitution of the interior of the earth is a subject of great
interest in the science of geography, as many of the visible forms upon
the crust have been wrought by the power of the agencies within it. The
discussion has been warm in the past, and doubtless will be resumed
with unabated interest as we find new phenomena for the argument. The
apparent lull that has followed the promulgation of the theory, three
years ago, that under the crust we should find a fluid, or semi-fluid,
surrounding a solid nucleus, may not be of long duration. This
hypothesis probably comes nearer to satisfying the conditions imposed
by the physicist and geologist, than those which have preceded it, and
may be accepted for the present; unless the processes of nature by
which it is conceived this state of the interior of the earth has been
produced, shall be demonstrated to have continued for sufficient time
to have caused a condition of equilibrium and possible solidification
of the whole sphere; when we might expect it to be repudiated by those
who oppose the theory of isostacy, but commended by the physicists as
supporting their claim that the earth must be substantially a solid
even now. If we accept Mr. Frederick Wright's suggestion, isostacy may
have an important bearing on the cause of the ice sheets that covered
such great areas; a suggestion that opens to the vision of the
imagination an orography beside which the grandest landscape we may see
to-day would pale into insignificance. This is believed to be a new
application of the isostatic theory, and may be a possible solution of
a much vexed question when an initial cause for such great upheavals
can be advanced that will not be inconsistent with other accepted
conditions.
Theories are modified by new facts, and in any attempt to demonstrate
the constitution of the interior of the earth, the increase of
temperature with the depth is an important factor. The recent measures,
therefore, in Germany, that indicate the figures generally accepted are
not reliable, may be received with interest. The shaft was sunk
especially for the purpose of observing temperatures at different
depths, and every precaution that former experience had suggested seems
to have been taken to secure accuracy. The greatest depth reached was
about one mile. An elaborate discussion of the results fixes the
increase of temperature at 1° F. for each 65 ft. increase of depth.
This is about 15 ft. greater than the figures that have heretofore been
given; a difference so large that we may question if they will be
generally accepted until verified by further observations made with
equally great care.
In conclusion permit me to note the fact that the United States was for
the first time represented in the International Geodetic Association,
at the meeting recently held in Paris; and also to record the
successful conclusion of the fourth International Geographical Congress
that assembled in Paris in August last. The reports from the Congress
indicate a wide range of subjects discussed, and lead us to believe the
interest in our science is progressive, and must receive the hearty
appreciation of all who are inspired by the nobler instincts to
develope the great sphere on which we live; that the riches, the
beauties, and above all the grandeur of Nature, may be made manifest to
ourselves and for our posterity.
REPORT--GEOGRAPHY OF THE AIR.
BY GEN. A. W. GREELY.
It is with a feeling of increased responsibility, shared doubtless by
the Presidents of other sections, that the Vice-President of the
Geography of the Air brings before you his modest annual contribution
in one branch of geographical science.
We live in an age so imbued with earnest thought, and so characterized
by patient investigation, that an eager gleaner in scientific fields
finds at the very outset his mind filled with the garnered grain of
golden facts. The more cautious searcher often follows with uncertain
mind, and doubtless in his backward glances sees many fairer and
heavier sheaves than those he bears with full arms, from the fruitful
harvest. If, then, you do not find here dwelt on such geographical
phases as you judge most important, attribute the fact I pray you, not
to neglect, but to lack of observation, or to the exercise of an
undiscriminating judgment.
First let us turn to the higher class of investigations, wherein that
handmaid of science, a true and noble imagination, comes to supplement
exact knowledge, to round out and give full form and perfect outline,
either shaping a number of disjointed and apparently heterogeneous
facts into a harmonious series, or evolving from a mass of confusing
and seemingly inexplicable phenomena a theory or law consistent
therewith.
In this domain Professor Ferrel's book on Winds is probably the most
important theoretical meteorological discussion of the past year. It
owes its value to the fact that it puts into comparatively simple and
popular form the processes and results of his intricate mathematical
investigations of the motions of the air, published by him years since,
and later elaborated during his service with the Signal Office.
In connection with the subject of winds, Professor William M. Davis has
formulated an excellent classification, depending first, on the
ultimate source of the energy causing the motion; second, on
temperature contrasts which produce and maintain winds; and third, on
their periodicity and the time of the first appearance of the motion.