James Monteith.

New physical geography : for grammar and high schools, and colleges online

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THE attention of Teachers and School Officers is respectfully called to the following;
special features of this book :

Its Easy Style and the Clearness of its Statements fit it for use not only in
3rammar Schools, but also in High and Normal Schools.

The Illustrations, executed by the best artists, serve not only to embellish the
work, but to impress vividly upon the mind of the learner the leading truths in this
most interesting science.

The Text contains the latest discoveries in Physiography, Meteorology, Hydrog-
raphy, Magnetism, and Vulcanology.

The Maps and Charts have been compiled from original sources, and from the
latest official maps of the United States and British Governments.

The subject of Magnetism contains much new matter never before published, the
material having been obtained from the records of the United States Magnetic Observa-
tory by the courtesy of Professor Marcus Baker.

The chapter on Volcanoes is based upon the researches of Professor Judd, the
highest authority on the subject of Vulcanology.

The subject of Ocean Currents contains the latest discoveries, including those
made by Commander Bartlett, of the U. S. Steamer Blake.

The chapter on Rivers and Drainage contains much that is new in the way of
Hydrography. The facts and figures have been obtained from the records of the U. S.
Engineer Corps.

The subject of Winds is based upon the researches of Professor Ferrel ; that of
Storms, upon the records of the United States Weather Bureau. The latter subject is the
most complete exposition of the Law of Storms that has yet appeared in a school
text-book. It contain^ hew ^n^'is&ipGrtant principles.

It is the only. Physical .Geography containing Bird's-eye Relief Maps.


Copyright. 188o. Oy JAMES MONTEITH.
v. \



I. -THE EARTH IN SPACE. Its Motions, etc. - - - - - 5

II. THE CRUST OF THE EARTH. Its Strata, etc. - - - - 11

III. THE LAND SURFACE OF THE EARTH. Its Continents, etc. - - 2O


V. ISLANDS. Reefs, Lagoons, etc. - 36

VI. MAGNETISM. The Mariner's Compass ; Magnetic Storms, etc. - 4O

VII. VOLCANOES AND VOLCANIC FORCES. Phenomena of Eruption ; Geysers, etc. 44

VIII. EARTHQUAKES. Their Causes and Effects 51

IX. THE WATER OF THE ATMOSPHERE. Its Forms and Uses - 56

X. THE WATERS OF THE CONTINENTS. Springs and Lakes - 62

XI. RIVERS AND DRAINAGE. What Rivers are and what they do 68

XII. AVALANCHES, GLACIERS, AND ICEBERGS. Their Formation and Powers. 75

XIII. OCEAN WATERS. Their Extent, Color, Waves, etc. _____ 81

XIV. TIDES. What' Causes them 86

XV. OCEAN CURRENTS. Their Formation and Influence - - - 90

XVI. THE ATMOSPHERE. Its Properties, Winds, Calms, etc. 96

XVII. STORMS, CYCLONES, AND TORNADOES. Their Nature and Effects - - 102


XIX. THE DISTRIBUTION OF LIFE - - -.- - - - - - - - -119

XX. MINERALS -___ - - - 130






ji diagram showing the paths and relative size of the various members of the Solar System
Ihe space included within this Orbit of Jupiter represents the proportionate size of the Sun,




1. Stars. Those bright, twinkling points of
light that we see in the sky after the Sun has
gone down, are huge balls of matter.

2. All of them are very far away, and some
are so distant that a ray of light, moving 186,000
miles every second, would not reach the earth for
many years after starting on its journey. 1

3. Nearly all of these heavenly bodies are
many times hotter than the hottest furnace-fire
so hot, indeed, that they exist either as molten
matter or else as a vapor. 3

4. A few of these balls of matter are con-
stantly changing their position in the sky. They
no longer give light of their own, but we see them
because the light of the sun falls on them, and is
reflected to our eves.

The Earth in Space.

5. They are called planets (from a Greek word meaning wanderer), and they are for-
ever whirling round and round the Sun.

6. The Earth is one of these Planets.

7. Fixed Stars. The Sun gives both light and heat to the family of planets whirling .
around him. The other bright bodies are called fixed stars.

8. All of the other Fixed Stars are suns, and there are many reasons for believing that
each has a family of worlds or planets revolving about it.

1 The nearest fixed star, excepting the Sun, is star a of the constellation Centaurus. Its light is three and one quarter
years in reaching the Earth.

2 Every substance exists in at least two of three states solid, liquid, or vapor. By heating iron it melts, and finally
ooils, giving off an orange-brown vapor or steain. Water may be easily changed to ice or to steam. By withdrawing the
heat, and at the same time applying great pressure, the air we breathe has been liquefied.


9. Our Sun and his group of worlds are called The Solar System.

10. The Solar System is composed of the Sun, eight worlds called planets, twenty
or more satellites or moons, and about 240 smaller planets called asteroids, besides comets
and meteors. 1








No. OF




35 750 000

88 days.



66 750 000

224 days.



92 300 000






1.9 y.






11.8 y.





29.5 y.



Uranus (u'ra-nus). .


84 y.




2 775 000,000

164 8 y.



11. Between Mars and Jupiter are about 240 small planets, called asteroids. They are
very small, none exceeding 300 miles in diameter.

12. Since the year 1600, more than 200 comets have been discovered.

13. A few comets belong to the Solar system, and travel around the Sun very much aa
the planets do. Others came from regions in space of which we have no knowledge, and
after passing partly around the Sun, went off into space, never to return.

14. Meteors are commonly called shooting stars. They may be seen on almost any
clear night, darting like balls of fire across the sky. 2

15. The planets in their order from the Sun, are named as follows : Mercury, Venus,
Earth, Mars, the Asteroids, Jupiter, Saturn, Uranus, and Neptune.

16. The line in the diagram on which each planet is situated shows its path around
the Sun.

17. All of the planets move around the Sun from west to east.

18. Their orbits or paths are ellipses, the Sun being at one focus or center.

19. Each of the planets turns on its axis from west to east.

1 The velocity of meteors is about forty miles per second. Moving with such a great velocity, when meteors strike
the Earth's atmosphere, the great heat developed not only melts, but vaporizes all^ but the largest ones. Many fall to the
Earth and are found. Some are composed chiefly of iron and nickel. Others are of the nature of stone. At least one comet
(Tempel's) has been proved to consist of an immense swarm of meteors moving in a cluster around the Sun.

8 It is usual, but hardly correct, to say that the planets revolve about the Sun. The truth is that all of the members
of the Solar System revolve about a common center of gravity.


20. The Earth and each planet beyond it are attended by one
or more moons.

21. Each moon moves around its planet in an elliptical path
from west to east.

22. So far as known, each moon turns on its axis from west
to east.

23. The Earth and probably the other planets, are composed
of the same elements that are found in the Sun. 1 Of many
meteors that have been analyzed, none has been found which con-
tains elements other than those which compose the Earth.

24. Thus it will be seen that the planets,in many respects, resemble one another. 2

25. They differ widely in their physical condition, however. Some are apparently hot
and fluid, while others are cold and solid.

26. Jupiter is still glowing with heat, and possibly gives a faint light to its five moons.
It is enveloped by dense clouds forming the bands or zones, which are seen in the picture.

27. Saturn is surrounded by several flat rings,
one outside of another, whirling swiftly around as
though they were the rims of immense fiery wheels.
It is thought that Saturn is a world yet in the process
of formation, and that the matter composing this
planet is partly fluid and partly solid.

28. Mars is a world very much like our own. Its
surface is diversified with oceans, seas, bays, conti-
nents, islands, and peninsulas. Through a good tele-
scope one may see the frozen zones of ice and snow,
one at the north, the other at the south pole. Its

position, with respect to the Sun, is such that the temperate zones of Mars have seasons
like ours.

29. The Moon. At least one of these heavenly bodies, the moon, has become cold from
surface to center. The air and water, if ever there were any, have disappeared. Its surface
is covered with immense craters, many of which exceed fifty miles in diameter. During the
hottest part of the moon's day, the temperature is nearly that of melting lead ; at night, it is
thought to be about 200 below zero.

30. The Sun. The Sun is a huge mass of matter more than 1,250,000 times greater than

Telescopic View of Saturn.

1 This has been discovered by analyzing the light of the Sun with the spectroscope. Sodium, potassium, iron, nickel,
hydrogen, and many other elements have been discovered in the Sun, and most of them also occur in several fixed stars.

2 It is thought by many students of nature, that all of the matter which composes the solar system was originally in
one mass of vapor ; that this matter began to gather around a center ; that a rotation around this center was acquired ;
that the mass of revolving vapor grew smaller in bulk as it cooled ; that finally, the rotation became so rapid that portions of
the mass were thrown off; that these portions, collecting in globular masses, formed the planets ; and that the planets, by
a similar process, threw off still smaller portions, which became moons. Although this is a supposition only, yet there are
many facts which make it worthy of belief.


Telescopic yiew of Moon.

the Earth. The spectroscope shows that it is
composed of substances similar to those found
in the Earth and the other planets.

31. These substances, however, owing to
the intense heat, are at the surface, in a gas-
eous or a fluid state.

32. With a powerful telescope, jets of gas
at a white heat may be seen projected to a

E distance of even 200,000 miles. The velocity
with which these immense columns of gas are
thrown upward, sometimes exceeds 250 miles
per second.

33. Sometimes, funnel-shaped, black spots
are seen on the Sun's surface. These spots
have exceeded 140,000 miles in diameter.
They are usually in violent agitation. In-
deed, the whole surface of the Sun appears to
be a tempestuous sea of white-hot metallic
vapors, and seething, molten elements.

34. In shape, the Earth is a slightly flattened sphere, bulging at the Equator. 1 This
has been shown in various ways.

35. Ships have sailed around it. The Earth's shadow is circular. A straight line sur-
veyed at the surface of the water apparently rises. In reality, the surface of the Earth
curves away from the line.

36. The Dimensions of the Earth are

as follows :

Diameter at the poles, 7899.2 miles.
Diameter at the equator, 7925.6 miles.
Circumference at the equator, 24,899 miles.
Surface, 197,000,000 square miles.
Volume, 260,000,000,000 cubic miles.

37. The Earth weighs about five times
as much as a globe of water of the same size.
Its density, therefore, is said to be 5. At the
surface, however, the density is only about 2| ;
that is, a cubic foot of matter composing the
surface is only 2% times as heavy as the same
bulk of water.

38. Hence it is thought that either the matter in the interior of the earth is compressed,
or else that it is composed of metallic substances.

Sun Spot. The size of the Earth is shown in one corner.

i In mathematics, such a solid is called an oblate spheroid. The Earth is not a true oblate spheroid, however, as recent
Investigations have shown that there is also a slight bulging at the temperate zones. This " square-shouldered " appearane*
10 also noticeable in Saturn and Jupiter.


39. The pupil who studies
the rocks that compose the sur-
face of the Earth will contin-
ually find fresh proofs that the
whole Earth was once at a glow-
ing white heat. 1

40. Motions. There is
nothing at rest in the Universe.
Suns, moons, and planets are
constantly whirling about their
common center, and all are at
the same time sweeping on
through space. The stars, too,
are in swift motion, each in his
own path, never for a moment

41. The Earth has two
motions. First, it turns on its
axis, causing day and night. 8

Second, it moves rapidly around the sun, making the complete journey in about 365J
days. 3

42. When nearest the Sun, the
Earth is said to be in perihelion ;
when farthest from the Sun, in

43. The Earth reaches its peri-
helion -about January 1st and its
aphelion, six months later. Its mo-
tion is most rapid while in peri-

44. The axis of the Earth is in-
clined 23 degrees toward the eclip-
tic, as may be seen in the diagram
at the top of the next page.

An ellipse, representing a distorted view of the Earth's orbit. E is the Earth; F is one
focus of the ellipse ; the Sun is at the other. The Earth is 3,000,000 miles nearer the
Sun at perihelion, than six months later.

The Succession of Day and Ni^ht. The lamp represents the Sun ; the apple, the
Earth ; the needle on which the apple turns represents the Axis of the Earth.

1 Although the temperature of the Earth's interior is far above the melting point of the most refractory substances,
it is by no means certain that it is in a " fluid " condition. On the contrary, tlie Earth, with respect to the Sun's attraction,
Tsehaves like a solid body.

2 The time required by the Earth to make a complete revolution is divided for convenience into twenty-four hours.
At the equator, the circumference of the Earth is nearly 25,000 miles, but the parallels decrease rapidly in length as they
-approach the poles. It is evident, therefore, that the velocity diminishes as the latitude increases, being greatest at the

In latitude 0, the velocity is 1,040 miles per hour ; in latitude 80", 896 miles ; in latitude 50, 665 miles; in latitude
70, 354 miles ; in latitude 80, 180 miles; and at the poles, it is 0.

8 The length of this journey around the sun is about 580,000,000 miles. This divided by 365 x 24 gives a quotient of
about 66,000 miles, the Earth's velocity in miles per hour. The velocity in one second is nearly 19 miles.

There is one other motion of the Earth, which, in great lengths of time, is thought to modify its climate. The poles of
the Earth are constantly moving around in a circle, in the same manner as does the upper pole of a sleeping top. This move-
ment is completed in 27,000 years.



The Earth's orbit as it would appear if viewed on a level with the Ecliptic, or plane of the orbit.

45. From the illustration on the preceding page, you will see that the Earth is nearest
the Sun during the winter of the Northern Hemisphere, where most of the land is situated.

46. The effect of this is not only to temper the extreme heat of summer, but also to
moderate the cold of winter in this hemisphere.

47. In respect to its distance from the Sun, the inclination of its axis, and its velocity,
the Earth seems better adapted than any other planet for the sustenance of life. 1


The stars are great masses of intensely hot
matter many million miles away.

The nearest fixed star is the Sun.

The Sun is attended by eight planets and
about 24:0 asteroids that are continually whirl-
ing about it.

There are also comets, some of which are a
part of the solar system, and innumerable me-
teors or shooting stars.

Most of the planets have cooled and no longer
give any light, but others are thought to be still
in a fluid condition, and perhaps to emit a faint

All the planets are like the Sun in shape, and
they resemble one another in their motions and
general properties.

All but two of them are attended by moons or
satellites, having form and motions like the
planets themselves.

Most, if not all of the planets are surrounded
by an atmospJiere.

The motions of each planet are principally a
spinning upon Us axis and a whirling around
the Sun.

The Earth measures about 25,OOO miles in
circumference, and nearly 8,OOO miles in di-
ameter. Its distance from the Sun is nearly
93,OOO,OOO miles.

It spins on its axis about 365 times while it
moves around the Sun once.

The first of these is the cause of the succes-
sion of day and night, the second causes the
change of seasons. 1

In its journey around the Sun, the Earth
moves at the rate of 6(i,OOO miles per hour.

The path of the Earth is an ellipse, the Sun
being at one of its foci or centers.

TJie Earth is about 3,OOO,OOO miles nearer
the Sun in winter than in summer.

1 We shall learn in chapters following, that life-forms have played an important part in the history of the world.
Many of the rocks have been formed through their agency; the present aspect of the Earth's surface is largely owing to the
work of plant and animal life. We need go only a few miles, either above or below the Earth's surface, to find conditions of
cold or of heat that would at once be fatal to any form of life with which we are acquainted. Yet, through all the changes-
and convulsions of nature, life-forms have not only held their place, but they have also steadily progressed to higher and
more complex stages. s The change of seasons is caused by the revolution of the Earth around the Sun, together with

the inclination of the Earth's axis in the same general direction, throughout the year.




1. It is thought that the Earth was once a seething, molten mass, and that through the-
course of long periods of time, the surface gradually cooled, until a solid crust formed on
the outside. 1

2. The thickness of the cooled crust of the Earth is estimated at from 55 miles to 250
miles. There are at the present time, however, no means whereby it may be measured wit T a
any certainty.

3. Condition of Interior. That the interior of the Earth is intensely hot, there i&
little or no doubt a fact which may be shown by several phenomena.

4. First, the shape of the Earth, slightly flattened at the poles, is such as would be
produced by the spinning of a partly fluid bocly on its axis.

5. Second, active volcanoes are found in all parts of the world. These throw large
quantities of melted matter from their craters.

6. Third, in sinking deep shafts and artesian wells, there is a gradual increase of
temperature, averaging 1 F. for about 53 feet. 2

7. Fourth, geysers and hot springs occur at various latitudes in every continent. The-
waters of these springs sink deep into the Earth through crevices and passages. When they
return to the surface, these waters are heated nearly or quite to the boiling point. Hence
they derive their heat from the Earth's interior. 3

8. Formative Processes. The student who studies the crust of the Earth will readily
believe that long periods of time have elapsed since the Earth took its present form.

1 Whether or not the interior of the Earth is in a fluid condition, is as yet a matter of speculation. The stronger
evidence certainly leads to the conclusion that the Earth is solid, or else plastic, from center to surface. Many mathematicians
are of the opinion that the great pressure from the outside towards the center that is, the enormous weight of the overlying
crust causes the heated interior to retain a condition of rigid solidity.

2 This increase in temperature is by no means uniform, but varies between 27 and 198 feet per degree. The rate of
increase is greater in mines than in artesian wells. In many instances, the rate of increase is very largely due to the heat
resulting from chemical decomposition. For instance, in the deep shafts of the Nevada silver mines, the temperature, on the
same levels of different mines, varies from 10 to 60. Beyond a depth of 2,000 feet, the average rate of increase is 1 for
every 165 feet.

The thickness of the Earth's crust cannot be estimated from these figures, however, as the melting point of solids-
varies with the pressure the greater the pressure, the higher the melting temperature. Besides, the crust of the Earth has-
never been penetrated more than one mile in depth, and it cannot be told whether or not the increase of temperature is the
same for all depths.

8 In many instances, however, hot springs derive their heat from the chemical changes going on among the rocks.


The parts of the map shown in white represent the first land of the United States.
"The pans in dark shading along the coasts remained under water until a more

recent period.
The dark shading inland were vast tracts of marsh and woodland, but now they are

the great coal fields of this country.

9. Nearly, if not all, of the dry
land has been again and again cov-
ered by the waters of the sea, and we
may also believe that what is now the
bed of the ocean has been more than
once lifted above the surface of the

10. Plant life in the greatest
luxuriance, and most wonderful in
form and size, has covered the face of
Earth and has been overwhelmed by
the waters.

11. Gigantic animals lived,
multiplied, and perished. Enormous
reptiles inhabited the immense swamps
and morasses which, during different
periods, covered large areas of the
Earth's surface. These perished, and
were succeeded by other forms of life,
and these, in turn, passed away, leav-
ing the story of their lives printed
upon the rocks.

12. Different climates succeeded one another. Parts of the Earth, at one period
covered with ferns, palms, and other tropical plants, were afterwards buried under the ice
and snow of a dreary winter that for centuries chilled the Earth's surface.

13. Immense glaciers, or rivers of ice, have rounded off the sharp hilltops and moun-
tain sides, and have ploughed deep gorges through the hardest rock.

14. Earthquakes and upheavals have raised large surfaces of land out of the waters,
and in other places, have sunk great areas until the sea covered them many fathoms deep.

15. Volcanoes and fissures have poured out floods of lava until immense areas of ter-
ritory have been covered to a great depth. 1

16. Running waters have worn their way through these sheets of lava and other
rock, cutting channels, sometimes exceeding a mile in depth, into the mountains and

The wind, blowing loose sand and dirt day after day and year after year, has filled up
seas, and in some cases has severed arms of the sea from the main body of water. Often it
has extended the shore for miles into the sea. 2

17. These changes, carved in the rocks by the forces of nature, have been going on for
ages. No one can measure the time in years ; it can be measured only in periods of un-

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Online LibraryJames MonteithNew physical geography : for grammar and high schools, and colleges → online text (page 1 of 15)