probable that Mars, Venus and Mercury have passed through periods
corresponding to our Ice Age; and that Jupiter, Saturn, Uranus and
Neptune have not reached theirs. A study of Jupiter in this connection
is particularly instructive. Phenomena are presented which are easily
explained by the theory under discussion. See Zenographical Fragments,
London, 1891. Also the author’s views in _Circulation of the Atmosphere
of Planets_. Trans. Technical Society of the Pacific Coast, Vol. XI,
No. 4, pp. 127-143.
[9] There were circumstances protecting certain areas, such as the
“Unglaciated Area,” in the basin of the Yellowstone River, in North
America. Here vast and continuous lava overflows in Wyoming, Idaho,
Oregon and Washington, liberated earth heat; which heat, borne easterly
by the general circulation of the atmosphere, caused the precipitation
upon the “Unglaciated Area” to be warm rains instead of snow. To
this region the animals of the tertiary period retreated as glacial
conditions surrounded them. Here they were protected, and perpetuated
their species, and in these regions vast quantities of their remains
are found. _Mining and Scientific Press_, Feb. 14, 1892.
The easterly projection of the unglaciated area is opposite the
corresponding projection in the lava overflow. How this simple
explanation has escaped the researches of geologists is not known.
[10] Maury, _Physical Geography of the Sea_, 6th Edition, p. 212, _et
seq._ Croll, _Climate and Time_, p. 60, _et seq._ Also, Climate and
Cosmology, p. 51.
[11] Except hydrogen.
[12] Moreover, in cooling the subjection of one pole to glacial and the
other to temperate or sub-tropical conditions, as argued by Dr. Croll,
would have subjected our planet to very peculiar “cooling strains,” as
they are termed by foundrymen. Whereas the slow and uniform cooling,
as herein described, is productive of maximum thickness, strength and
uniformity of crust; and, as will be explained later, this crust was
finally shrunk in upon the interior mass by being subjected to the
maximum degree of cold to which it can be exposed during the existence
of the sun as a source of heat.
[13] The prime objection which is urged against all previous theories
is their inadequacy. We here have a perfectly adequate cause--resident
earth heat to supply evaporation and shut out solar energy, which
energy can only act the part of a conservator of the glacial conditions
until the exhaustion of earth heat, when its power can be spent
in melting glacial ice, and in gradually establishing the present
conditions.
[14] It will again be noted that the isotherms inside of 32° - y° Far.
were maintained by earth heat, and therefore independent of equatorial
or polar exposure to solar heat. Consequently their intersections were
upon different lines from those isotherms exterior to 32° - y° Far.,
which latter were mainly dependent upon solar heat. It will also be
observed that solar heat, when it reaches the lower, denser regions of
the atmosphere, is trapped and therefore capable of establishing and
maintaining higher temperatures than in the upper atmosphere.
[15] The truth of this fact is easily established by either
observation or experiment. At the close of a hot day should a slight
cloudiness supervene, the loss of heat by radiation from the surface
is checked; the air at the surface, and the surface, remain at the
same temperature, and nature’s delicate differential thermometer--the
deposition or non-deposition of dew--records the non-transcalency of
clouds, in terms worthy of consideration.
Again, let two delicate thermometers be exposed, one to the air
temperature and the other in addition to direct solar rays; the latter
will mark the increased temperature due to such exposure. Upon the
intervention of a cloud, or even a jet of steam, both instruments will
mark the same temperature.
See Physical Geography of the Sea. Maury, 6th ed., p. 212, _et seq._
Climate and Time, Croll, p. 60, _et seq._
Climate and Cosmology, Croll, p. 51.
[16] Astronomers agree that there must exist upon Jupiter a high degree
of heat, and yet no refinement of thermometric determinations can
detect any more heat from the Jovian surface than should be reflected
from the sun.--See _Young’s General Astronomy_, page 353; also _History
of Astronomy During the Nineteenth Century_. Clerke, pp. 335-338.
[17] The author is aware that this statement is at variance with the
opinion of many Geologists of high repute, as may be seen from the
following quotations: “It is evident that the idea of connecting
the phenomena of the internal heat of the globe with terrestrial
climates, whether of the present or of past geological ages, must be
entirely abandoned, as it has been, by most writers on this subject.
The hypothesis cannot be allowed to stand as even one of the possible
theories of climatic change.”--_The Climatic Changes of later
Geological Times._ Whitney, p. 261.
“The first theory brought forward to account for glaciation was that
the earth, having been originally in a fiery state, had in cooling
passed from a condition of universal warmth to a more and more frigid
state, until the present conditions were attained. This is the least
tenable of all theories, for it neglected the now evident fact that
there had been changes from cold to warmth and back again to cold.
However, as it was invented before the existence of glacial periods was
suspected, it long commanded a general assent, and was the opinion that
held the ground until near the middle of this century.”--_Glaciers._
Shaler & Davis, p. 70.
The physicists who have held that earth heat was a cause of the Ice Age
are Prof. E. Frankland, F. R. S., Prof. A. Woeikof and Startorius von
Walterhausen. Not one of the three, however, seems to have had a clear
conception of all the facts and conditions although their views were in
the main sound.
The author hopes to extend the views held by these writers and to show
that the whole range of climates as recorded by fossil and existing
life is capable of correct interpretation, in accordance with known
laws, and without the intervention of suppositions and assumptions.
And moreover, to base his deductions upon a general plan applicable to
any planet and capable of explaining conditions prevalent upon other
planets, notably upon Jupiter and Mars.
[18] To those interested in a verification of this very wide
distribution of glaciation, the following short list of authorities is
recommended:
_Asia._--The Great Ice Age (Giekie); Note on the Glaciation of parts
of the Valleys of Jhelan and Scind Rivers, in the Himalaya Mountains
of Kashmere, Lat. 34° N. (Capt. A. W. Sleff), F. G. S.; Jour. Geol.
Soc., London, vol. xlvi, p. 66; Mem. Geol. Survey of India, vol. xxii,
also vol. xiv; Record Geol. Survey of India, Nov., 1880; Jour. Asiatic
Society, Bengal, xxxvi, p. 113; Brit. Association Report, 1880; Text
Book of Geology, A. Giekie, LL. D., etc., p. 911.
_Europe._--The European Glacial Literature is too extensive to mention.
_America._--The Ice Age in North America (Wright); U. S. Geological
Reports; State Geological Reports of Ohio, Kentucky, Pennsylvania, New
York, Minnesota, Nebraska, Colorado, Illinois, etc.; Virginia, Am.
Jour. Sci., vol. vi, p. 371; California, Am. Jour. Sci., vol. iii, p.
325, vol. x, p. 26.
_South America._--Geological Sketches, Agassiz, p. 154, _et seq._;
Geol. and Physical Geog. of Brazil (Prof. Ch. Fred. Hartt), pp. 22,
28-9, 469-70, 490, 558.
_Africa._--Geol. of South Africa (Stow); Quart. Journ. Geol. Soc.,
London, vols. xvii and xviii.
_Australia and New Zealand._--Climate and Time (Croll), p. 295; Am.
Jour. Sci., vol. 32, third series, p. 224; Proc. Linnæan Soc., N. S.
W., May, 1886; Prestwich’s Geol., vol. ii, p. 467; Rep. Brit. Assn.,
1881, p. 742.
“The shrunken or vanished ice of mountain ranges is indeed equally
characteristic of the Himalaya, the Lebanon, the Alps, the Scandinavian
chain, the great chains of North and South America, and of other minor
ranges and clusters of mountains.”--Ramsay, Quart. Jour. Geol. Soc.,
1862, p. 204.
[19] Many geologists are misled by the greater modification of tropical
drift by sub-aerial agencies. Having been longer exposed to such
agencies, greater modifications are to be expected. The apparent
improbability of tropical glaciation seems to deter many scientists
from believing that such glaciation could ever have occurred, yet the
same scientists will accept the fact that fossil life establishes
the existence of tropical or even torrid conditions within the polar
circles during past ages.
[20] See Geological Sketches, Agassiz, p. 154, _et seq._ Also Physical
Geography and Geology of Brazil, Prof. Ch. Fred. Hartt, pp. 22, 28, 29,
217, 469, 470.
[21] See the author’s views in _Physical and Geological Traces of
Permanent Cyclone Belts_. Trans. Technical Society of the Pacific
Coast, Vol. VIII, No. 1, June, 1891.
[22] Phil. Mag. (4), Vol. XXV, pp. 1-14. Trans. Royal Soc. Edin., Vol.
XXIII. Influence of the Earth’s Secular Heat upon Climates. Hopkins,
Jour. Geol. Soc., Vol. VIII.
[23] Climate and Time, Climate and Cosmology.
[24] The Cause of an Ice Age, chapters 5 and 6.
[25] Nature, May 1891; S. E. Bishop.
[26] Circulation of the Atmosphere of Planets.--Trans. Technical Soc.
of the Pac. Coast, Vol. IX, No. 5; pp. 136-143.
[27] For a further discussion of the conditions prevalent upon Jupiter
see _Circulation of the Atmosphere of Planets_, previously quoted.
[28] Except hot or warm lava covered areas, and the protected or
“unglaciated areas” to the eastward of such lava overflows. (See page
44 and note [9] page 14.)
[29] The Columbian Lava Plains of North America aggregate some 150,000
square miles; the Deccan Lava Plains of India cover an almost unbroken
plain 200,000 square miles in area. No Geologists ascribe these lava
overflows to an earlier date than the Tertiary; the author could find
no reason to assign the Columbian Lava Plain to so early a period,
and strong reasons to assign the continuance of the flow to the later
Quaternary; of the Deccan Plain he is unable to speak. (See Trans.
Geological Society of Australasia, vol. i, part vi, p. 162, note. Also
Mining and Scientific Press, Feb. 6th, 1892.)
[30] _Climatic changes indicated by Glaciers._
Prof. I. C. Russell, Am. Geologist, May, 1892, vol. ix, No. 5. In
addition to the very extensive list of authorities there quoted by
Prof. Russell, see also Report of The British Ass’n. 1881, p. 742.
Life of Agassiz, Vol. II, pp. 717 to 729 and pp. 743 to 747.
[31] At the culmination of the Ice Age evaporation reached its
minimum, and hence precipitation was also at a minimum. Since that
Age evaporation has slowly increased; the amount of moisture in the
atmosphere being dependant upon its temperature, this amount has also
increased. The aggregate amount of evaporation and the aggregate amount
of precipitation is slowly increasing, and has the moderate limit fixed
by natural laws for increase of mean temperature. Mars appears to have
progressed further in this mean condition than the earth. The smaller
mass partly accounts for this.
[32] Archives des Sciences, vol. v, p. 293. Proc. Royal Soc., vol.
xiii, p. 160.
[33] Archives des Sciences, Berne, vol. lvii, p. 293, _et seq._
[34] Dr. Cleveland Abbe, U. S. Meteorological Bureau. Am. Jour. of
Science, May, 1892, vol. xliii, p. 364.
[35] The albedo of Jupiter is 0.62; that of Mars, 0.26, of the moon
0.174. It will be observed that the planets distinctly shrouded in
clouds have high reflective powers; those planets and satellites not
shrouded have very low powers. Venus, in this respect, seems to have a
partially obscured atmosphere, her albedo being 0.50.
[36] General Astronomy.--Young; p. 337.
[37] Venus presents a condition which suggests that she may be partly
shrouded in clouds, shutting out solar heat, just as the thermal
equator of the earth is thus partly protected by the equatorial cloud
ring.
TRANSCRIBER’S NOTE
Page 6: “unequal subaerial denudation” changed to “unequal sub-aerial
denudation”
Page 16: “two spheroidal iostherms” changed to “two spheroidal
isotherms”
Page 25: “whole system of preglacial” changed to “whole system of
pre-glacial”
Page 30: “at variance with those ante-dating” changed to “at variance
with those antedating”
Page 31: “less in the Antartic” changed to “less in the Antarctic”
Page 33: “lowered one hundreed” changed to “lowered one hundred”
Page 35: “way into a subtropical growth” changed to “way into a
sub-tropical growth”
Page 35: “are really coroborative” changed to “are really
corroborative”
Page 46: “maintaining the cloud envelop” changed to “maintaining the
cloud envelope”
Page 48: “light received by the earth” changed to “light received by
the earth.”
Footnote 4: “la Mer. Déluges Périodique” changed to “la Mer. Déluges
Périodiques”