M. Boucher de Perthes, the first and most exhaustive investigator of these deposits, has always been of opinion that the drift-gravels of France were deposited by violent cataclysms.[1]

This view seems to be confirmed by the fact that the gravel-beds in which these remains of man and extinct animals are found lie at an elevation of from eighty to two hundred feet above the present water-levels of the valleys.

Sir John Lubbock says:

"Our second difficulty still remains—namely, the height at which the upper-level gravels stand above the

[1. "Mm. Soc. d'Em. l'Abbeville," 1861, p. 475.]

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present water-line. We can not wonder that these beds have generally been attributed to violent cataclysms."[1]

In America, in Britain, and in Europe, the glacial deposits made clean work of nearly all animal life. The great mammalia, too large to find shelter in caverns, were some of them utterly swept away, while others never afterward returned to those regions. In like manner palolithic man, man of the rude and unpolished flint implements, the contemporary of the great mammalia, the mammoth, the hippopotamus, and the rhinoceros, was also stamped out, and the cave-deposits of Europe show that there was a long interval before be reappeared in those regions. The same forces, whatever they were, which "smashed" and "pounded" and "contorted" the surface of the earth, crushed man and his gigantic associates out of existence.[2]

But in Siberia, where, as we have seen, some of the large mammalia were caught and entombed in ice, and preserved even to our own day, there was no "smashing" and "crushing" of the earth, and many escaped the snow-sheets, and their posterity survived in that region for long ages after the Glacial period, and are supposed only to have disappeared in quite recent times. In fact, within the last two or three years a Russian exile declared that he had seen a group of living mammoths in a wild valley in a remote portion of that wilderness.

These, then, good reader, to recapitulate, are points that seem to be established:

I. The Drift marked a world-convulsing catastrophe. It was a gigantic and terrible event. It was something quite out of the ordinary course of Nature's operations.

II. It was sudden and overwhelming.

[1. "Prehistoric Times," p. 372.

2. "The Great Ice Age," p. 466.]

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III. It fell upon land areas, much like our own in geographical conformation; a forest-covered, inhabited land; a glorious land, basking in perpetual summer, in the midst of a golden age.

Let us go a step further.

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CHAPTER VIII.

GREAT HEAT A PREREQUISITE.

Now, it will be observed that the principal theories assigned for the Drift go upon the hypothesis that it was produced by extraordinary masses of ice—ice as icebergs, ice as glaciers, or ice in continental sheets. The scientists admit that immediately preceding this Glacial age the climate was mild and equable, and these great formations of ice did not exist. But none of them pretend to say how the ice came or what caused it. Even Agassiz, the great apostle of the ice-origin of Drift, is forced to confess:

"We have, as yet, no clew to the source of this great and sudden change of climate. Various suggestions have been made—among others, that formerly the inclination of the earth's axis was greater, or that a submersion of the continents under water might have produced a decided increase of cold; but none of these explanations are satisfactory, and science has yet to find any cause which accounts for all the phenomena connected with it."[1]

Some have imagined that a change in the position of the earth's axis of rotation, due to the elevation of extensive mountain-tracts between the poles and the equator, might have caused a degree of cold sufficient to produce the phenomena of the Drift; but Geikie says—

"It has been demonstrated that the protuberance of the earth at the equator so vastly exceeds that of any

[1. "Geological Sketches," p. 210.]

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possible elevation of mountain-masses between the equator and the poles, that any slight changes which may have resulted from such geological causes could have had only an infinitesimal effect upon the. general climate of the globe."[1]

Let us reason together:—

The ice, say the glacialists, caused the Drift. What caused the ice? Great rains and snows, they say, falling on the face of the land. Granted. What is rain in the first instance? Vapor, clouds. Whence are the clouds derived? From the waters of the earth, principally from the oceans. How is the water in the clouds transferred to the clouds from the seas? By evaporation. What is necessary to evaporation? Heat.

Here, then, is the sequence:

If there is no heat, there is no evaporation; no evaporation, no clouds; no clouds, no rain; no rain, no ice; no ice, no Drift.

But, as the Glacial age meant ice on a stupendous scale, then it must have been preceded by heat on a stupendous scale.

Professor Tyndall asserts that the ancient glaciers indicate the action of heat as much as cold. He says:

"Cold will not produce glaciers. You may have the bitterest northeast winds here in London throughout the winter without a single flake of snow. Cold must have the fitting object to operate upon, and this object—the aqueous vapor of the air—is the direct product of heat. Let us put this glacier question in another form: the latent heat of aqueous vapor, at the temperature of its production in the tropics, is about 1,000 Fahr., for the latent heat augments as the temperature of evaporation descends.

A pound of water thus vaporized at the equator has absorbed one thousand times the quantity of heat which

[1. "The Great Ice Age," p. 98.]

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would raise a pound of the liquid one degree in temperature. . . . It is perfectly manifest that by weakening the sun's action, either through a defect of emission or by the steeping of the entire solar system in space of a low temperature, we should be cutting off the glaciers at their source."[1]

Mr. Croll says:

"Heat, to produce evaporation, is just as essential to the accumulation of snow and ice as cold to produce condensation."[2]

Sir John Lubbock says:

"Paradoxical as it may appear, the primary cause of the Glacial epoch may be, after all, an elevation of the temperature in the tropics, causing a greater amount of evaporation in the equatorial regions, and consequently a greater supply of the raw material of snow in the temperate regions during the winter months."[3]

So necessary did it appear that heat must have come from some source to vaporize all this vast quantity of water, that one gentleman, Professor Frankland,[4] suggested that the ocean must have been rendered hot by the internal fires of the earth, and thus the water was sent up in clouds to fall in ice and snow; but Sir John Lubbock disposes of this theory by showing that the fauna of the seas during the Glacial period possessed an Arctic character. We can not conceive of Greenland shells and fish and animals thriving in an ocean nearly at the boiling-point.

A writer in "The Popular Science Monthly"[5] says:

"These evidences of vast accumulations of ice and snow on the borders of the Atlantic have led some theorists

[1. "Heat considered as a Mode of Motion," p. 192.

2. "Climate and Time," p. 74.

3. "Prehistoric Times," p. 401.

4. "Philosophical Magazine," 1864, p. 328.

5. July, 1876, p. 288.]

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to suppose that the Ice period was attended, if not in part caused, by a far more abundant evaporation from the surface of the Atlantic than takes place at present; and it has even been conjectured that submarine volcanoes in the tropics might have loaded the atmosphere with an unusual amount of moisture. This speculation seems to me, however, both improbable and superfluous; improbable, because no traces of any such cataclysm have been discovered, and it is more than doubtful whether the generation of steam in the tropics, however large the quantity, would produce glaciation of the polar regions. The ascent of steam and heated air loaded with vapor to the altitude of refrigeration would, as it seems to me, result in the rapid radiation of the heat into space, and the local precipitation of unusual quantities of rain; and the effect of such a catastrophe would be slowly propagated and feebly felt in the Arctic and Antarctic regions.

When we consider the magnitude of the ice-sheets which, it is claimed by the glacialists, covered the continents during the Drift age, it becomes evident that a vast proportion of the waters of the ocean must have been evaporated and carried into the air, and thence cast down as snow and rain. Mr. Thomas Belt, in a recent number of the "Quarterly Journal of Science," argues that the formation of ice-sheets at the poles must have lowered the level of the oceans of the world two thousand-feet!

The mathematician can figure it out for himself: Take the area of the continents down to, say, latitude 40, on both sides of the equator; suppose this area to be covered by an ice-sheet averaging, say, two miles in thickness; reduce this mass of ice to cubic feet of water, and estimate what proportion of the ocean would be required to be vaporized to create it. Calculated upon any basis, and it follows that the level of the ocean must have been greatly lowered.

What a vast, inconceivable accession of heat to our

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atmosphere was necessary to lift this gigantic layer of ocean-water out of its bed and into the clouds!

The ice, then, was not the cause of the cataclysm; it was simply one of the secondary consequences.

We must look, then, behind the ice-age for some cause that would prodigiously increase the heat of our atmosphere, and, when we have found that, we shall have discovered the cause of the drift-deposits as well as of the ice.

The solution of the whole stupendous problem is, therefore, heat, not cold.

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PART II.

The Comet.

CHAPTER I.

A COMET CAUSED THE DRIFT.

Now, good reader, we have reasoned together up to this point. To be sure, I have done most of the talking, while you have indulged in what the Rev. Sydney Smith called, speaking of Lord Macaulay, "brilliant flashes of silence."

But I trust we agree thus far that neither water nor ice caused the Drift. Water and ice were doubtless associated with it, but neither produced it.

What, now, are the elements of the problem to be solved?

First, we are to find something that instantaneously increased to a vast extent the heat of our planet, vaporized the seas, and furnished material for deluges of rain, and great storms of snow, and accumulations of ice north and south of the equator and in the high mountains.

Secondly, we are to find something that, coming from above, smashed, pounded, and crushed "as with a maul," and rooted up as with a plow, the gigantic rocks of the surface, and scattered them for hundreds of miles from their original location.

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Thirdly, we are to find something which brought to the planet vast, incalculable masses of clay and gravel, which did not contain any of the earth's fossils; which, like the witches of Macbeth,

Look not like th' inhabitants of earth, And yet are on it; "

which are marked after a fashion which can not be found anywhere else on earth; produced in a laboratory which has not yet been discovered on the planet.

Fourthly, we are to find something that would produce cyclonic convulsions upon a scale for which the ordinary operations of nature furnish us no parallel.

Fifthly, we are to find some external force so mighty that it would crack the crust of the globe like an eggshell, lining its surface with great rents and seams, through which the molten interior boiled up to the light.

Would a comet meet all these prerequisites?

I think it would.

Let us proceed in regular order.

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CHAPTER II.

WHAT IS A COMET?

IN the first place, are comets composed of solid, liquid, or gaseous substances? Are they something, or the next thing to nothing?

It has been supposed by some that they are made of the most attenuated gases, so imponderable that if the earth were to pass through one of them we would be unconscious of the contact. Others have imagined them to be mere smoke-wreaths, faint mists, so rarefied that the substance of one a hundred million miles long could, like the genie in the Arabian story, be inclosed in one of Solomon's brass bottles.

But the results of recent researches contradict these views:

Padre Secchi, of Rome, observed, in Donati's comet, of 1858, from the 15th to the 22d of October, that the nucleus threw out intermittingly from itself appendages having the form of brilliant, coma-shaped masses of incandescent substance twisted violently backward. He accounts for these very remarkable changes of configuration by the influence first of the sun's heat upon the comet's substance as it approached toward perihelion, and afterward by the production in the luminous emanations thus generated of enormous tides and perturbation derangements. Some of the most conspicuous of these luminous developments occurred on October 11th, when the comet was at its nearest approach to the earth, and on

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October 17th, when it was nearest to the planet Venus. He has no doubt that the close neighborhood of the earth and Venus at those times was the effective cause of the sudden changes of aspect, and that those changes of aspect may be accepted as proof that the comet's substance consists of "really ponderable material."

Mr. Lockyer used the spectroscope to analyze the light of Coggia's comet, and he established beyond question that—

"Some of the rays of the comet were sent either from solid particles, or from vapor in a state of very high condensation, and also that beyond doubt other portions of the comet's light issue from the vapor shining by its own inherent light. The light coming from the more dense constituents, and therefore giving a continuous colored spectrum, was, however, deficient in blue rays, and was most probably emitted by material substance at the low red and yellow stages of incandescence."

Padre Secchi, at Rome, believed he saw in the comet "carbon, or an oxide of carbon, as the source of the bright luminous bands," and the Abb Moigno asks whether this comet may not be, after all, "un gigantesque diamant volatilis."

"Whatever may be the answer hereafter given to that question, the verdict of the spectroscope is clearly to the effect that the comet is made up of a commingling of thin vapor and of denser particles, either compressed into the condition of solidification, or into some physical state approaching to that condition, and is therefore entirely in accordance with the notion formed on other grounds that the nucleus of the comet is a cluster of solid nodules or granules, and that the luminous coma and tail are jets and jackets of vapor, associated with the more dense ingredients, and swaying and streaming about them as heat and gravity, acting antagonistic ways, determine."[1]

[1. "Edinburgh Review," October, 1874, p. 210.]

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If the comet shines by reflected light, it is pretty good evidence that there must be some material substance there to reflect the light.

"A considerable portion of the light of the comet is, nevertheless, borrowed from the sun, for it has one property belonging to it that only reflected light can manifest. It is capable of being polarized by prisms of double-refracting spar. Polarization of this character is only possible when the light that is operated upon has already been reflected from an imperfectly transparent medium."[1]

There is considerable difference of opinion as to whether the bead of the comet is solid matter or inflammable gas.

"There is nearly always a point of superior brilliancy perceptible in the comet's head, which is termed its nucleus, and it is necessarily a matter of pressing interest to determine what this bright nucleus is; whether it is really a kernel of hard, solid substance, or merely a whiff of somewhat more condensed vapor. Newton, from the first, maintained that the comet is made partly of solid substance, and partly of an investment of thin, elastic vapors. If this is the case, it is manifest that the central nodule of dense substance should be capable of intercepting light when it passes in front of a more distant luminary, such as a fixed star. Comets, on this account, have been watched very narrowly whenever they have been making such a passage. On August 18, 1774, the astronomer Messier believed that he saw a second bright star burst into sight from behind the nucleus of a comet which had concealed it the instant before. Another observer, Wartmann, in the year 1828, noticed that the light of an eighth-magnitude star was temporarily quenched as the nucleus of Encke's comet passed over it."[2]

Others, again, have held that stars have been seen through the comet's nucleus.

[1. "Edinburgh Review," October, 1874, p. 207.

2. Ibid., p. 206.]

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Amde Guillemin says:

"Comets have been observed whose heads, instead of being nebulous, have presented the appearance of stars, with which, indeed, they have been confounded."[1]

When Sir William Herschel discovered the planet Urania, he thought it was a comet.

Mr. Richard A. Proctor says:

"The spectroscopic observations made by Mr. Huggins on the light of three comets show that a certain portion, at least, of the light of these objects is inherent. . . . The nucleus gave in each case three bands of light, indicating that the substances of the nuclei consisted of glowing vapor."[2]

In one case, the comet-head seemed, as in the case of the, comet examined by Padre Secchi, to consist of pure carbon.

In the great work of Dr. H. Schellen, of Cologne, annotated by Professor Huggins, we read:

"That the nucleus of a comet can not be in itself a dark and solid body, such as the planets are, is proved by its great transparency; but this does not preclude the possibility of its consisting of innumerable solid particles separated from one another, which, when illuminated by the sun, give, by the reflection of the solar light, the impression of a homogeneous mass. It has, therefore, been concluded that comets are either composed of a substance which, like gas in a state of extreme rarefaction, is perfectly transparent, or of small solid particles individually separated by intervening spaces through which the light of a star can pass without obstruction, and which, held together by mutual attraction, as well as by gravitation toward a denser central conglomeration, moves through space like a cloud of dust. In any case the connection lately noticed by Schiaparelli, between comets and meteoric

[1. "The Heavens," p. 239.

2. Note to Guillemin's "Heavens," p. 261.]

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showers, seems to necessitate the supposition that in many comets a similar aggregation of particles seems to exist."[1]

I can not better sum up the latest results of research than by giving Dr. Schellen's words in the work just cited:

"By collating these various phenomena, the conviction can scarcely be resisted that the nuclei of comets not only emit their own light, which is that of a glowing gas, but also, together with the coma and the tail, reflect the light of the sun. There seems nothing, therefore, to contradict the theory that the mass of a comet may be composed of minute solid bodies, kept apart one from another in the same way as the infinitesimal particles forming a cloud of dust or smoke are held loosely together, and that, as the comet approaches the sun, the most easily fusible constituents of these small bodies become wholly or partially vaporized, and in a condition of white heat overtake the remaining solid particles, and surround the nucleus in a self-luminous cloud of glowing vapor."[2]

Here, then, we have the comet:

First, a more or less solid nucleus, on fire, blazing, glowing.

Second, vast masses of gas heated to a white heat and enveloping the nucleus, and constituting the luminous head, which was in one case fifty times as large as the moon.

Third, solid materials, constituting the tail (possibly the nucleus also), which are ponderable, which reflect the sun's light, and are carried along under the influence of the nucleus of the comet.

Fourth, possibly in the rear of all these, attenuated volumes of gas, prolonging the tail for great distances.

What are these solid materials?

[1. "Spectrum Analysis," 1872.

2. Ibid., p. 402.]

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Stones, and sand, the finely comminuted particles of stones ground off by ceaseless attrition.

What is the proof of this?

Simply this: that it is now conceded that meteoric showers are shreds and patches of cometic matter, dropped from the tail; and meteoric showers are stones.

"Schiaparelli considers meteors to be dispersed portions of the comet's original substance; that is, of the substance with which the comet entered the solar domain. Thus comets would come to be regarded as consisting of a multitude of relatively minute masses."[1]

Now, what is the genesis of a comet? How did it come to be? How was it born?

In the first place, there are many things which would connect them with our planets.

They belong to the solar system; they revolve around the sun.

Says Amde Guillemin:

"Comets form a part of our solar system. Like the. planets, they revolve about the sun, traversing with very variable velocities extremely elongated orbits."[2]

We shall see reason to believe that they contain the same kinds of substances of which the planets are composed.

Their orbits seem to be reminiscences of former planetary conditions:

"All the comets, having a period not exceeding seven years, travel in the same direction around the sun as the planets. Among comets with periods less than eighty years long, five sixths travel in the same direction as the planets."[3]

[1. "American Cyclopdia," vol. v, p. 141.

2. "The Heavens," p. 239.

3. American Cyclopedia," vol. v, p. 141.]

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It is agreed that this globe of ours was at first a gaseous mass; as it cooled it condensed like cooling steam into a liquid mass; it became in time a molten globe of red-hot matter. As it cooled still further, a crust or shell formed around it, like the shell formed on an egg, and on this crust we dwell.

While the crust is still plastic it shrinks as the mass within grows smaller by further cooling, and the wrinkles so formed in the crust are the depths of the ocean and the elevations of the mountain-chains.

But as ages go on and the process of cooling progresses, the crust reaches a density when it supports itself, like a couple of great arches; it no longer wrinkles; it no longer follows downward the receding molten mass within; mountains cease to be formed; and at length we have a red-hot ball revolving in a shell or crust, with a space between the two, like the space between the dried and shrunken kernel of the nut and the nut itself.

Volcanoes are always found on sea-shores or on islands. Why? Through breaks in the earth the sea-water finds its way occasionally down upon the breast of the molten mass; it is at once converted into gas, steam; and as it expands it blows itself out through the escape-pipe of the volcano; precisely as the gas formed by the gunpowder coming in contact with the fire of the percussion-cap, drives the ball out before it through the same passage by which it had entered. Hence, some one has said, "No water, no volcano."

While the amount of water which so enters is small because of the smallness of the cavity between the shell of the earth and the molten globe within, this process is carried on upon a comparatively small scale, and is a safe one for the earth. But suppose the process of cooling to go on uninterruptedly until a vast space exists between the

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crust and the core of the earth, and that some day a convulsion of the surface creates a great chasm in the crust, and the ocean rushes in and fills up part of the cavity; a tremendous quantity of steam is formed, too great to escape by the aperture through which it entered, an explosion takes place, and the crust of the earth is blown into a million fragments.

The great molten ball within remains intact, though sorely torn; in its center is still the force we call gravity; the fragments of the crust can not fly off into space; they are constrained to follow the master-power lodged in the ball, which now becomes the nucleus of a comet, still blazing and burning, and vomiting flames, and wearing itself away. The catastrophe has disarranged its course, but it still revolves in a prolonged orbit around the sun, carrying its broken dbris in a long trail behind it.

This dbris arranges itself in a regular order: the largest fragments are on or nearest the head; the smaller are farther away, diminishing in regular gradation, until the farthest extremity, the tail, consists of sand, dust, and gases. There is a continual movement of the particles of the tail, operated upon by the attraction and repulsion of the sun. The fragments collide and crash against each other; by a natural law each stone places itself so that its longest diameter coincides with the direction of the motion of the comet; hence, as they scrape against each other they mark each other with lines or stri, lengthwise of their longest diameter. The fine dust ground out by these perpetual collisions does not go off into space, or pack around the stones, but, still governed by the attraction of the head, it falls to the rear and takes its place, like the small men of a regiment, in the farther part of the tail.

Now, all this agrees with what science tells us of the constitution of clay.

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"It is a finely levigated silico-aluminous earth—formed by the disintegration of feldspathic or granite rocks."[1]

The particles ground out of feldspar are finer than those derived from mica and hornblende, and we can readily understand how the great forces of gravity, acting upon the dust of the comet's tail, might separate one from the other; or how magnetic waves passing through the comet might arrange all the particles containing iron by themselves, and thus produce that marvelous separation of the constituents of the granite which we have found to exist in the Drift clays. If the destroyed world possessed no sedimentary rocks, then the entire material of the comet would consist of granitic stones and dust such as constitutes clays.

The stones are reduced to a small size by the constant attrition:

"The stones of the 'till' are not of the largest; indeed, bowlders above four feet in diameter are comparatively seldom met with in the till."[2]

And this theory is corroborated by the fact that the eminent German geologist, Dr. Hahn, has recently discovered an entire series of organic remains in meteoric stones, of the class called chrondites, and which he identifies as belonging to classes of sponges, corals, and crinoids. Dr. Weinland, another distinguished German, corroborates these discoveries; and he has also found fragments in these stones very much like the youngest marine chalk in the Gulf of Mexico; and he thinks he sees, under the microscope, traces of vegetable growth. Francis Birgham says:

[1. "American Cyclopdia," article "Clay."

2. "The Great Ice Age," p. 10.]

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"This entire ex-terrestrial fauna hitherto discovered, which already comprises about fifty different species, and which originates from different meteoric falls, even from some during the last century, conveys the impression that it doubtlessly once formed part of a single ex-terrestrial-celestial body with a unique creation, which in by-gone ages seems to have been overtaken by a grand catastrophe, during which it was broken up into fragments."[1]

When we remember that meteors are now generally believed to be the droppings of comets, we come very near to proof of the supposition that comets are the dbris of exploded planets; for only on planets can we suppose that life existed, for there was required, for the growth of these sponges, corals, and crinoids, rocks, earth, water, seas or lakes, atmosphere, sunshine, and a range of temperature between the degree of cold where life is frozen up and the degree of heat in which it is burned up: hence, these meteors must be fragments of bodies possessing earth-like conditions.

We know that the heavenly bodies are formed of the same materials as our globe.

Dana says:

"Meteoric stones exemplify the same chemical and crystallographic laws as the rocks of the earth, and have afforded no new element or principle of any kind."[2]

It may be presumed, therefore, that the granite crust of the exploded globe from which some comet was created was the source of the finely triturated material which we know as clay.

But the clays are of different colors—white, yellow, red, and blue.

[1. "Popular Science Monthly," November, 1881, p. 86.

2. "Manual of Geology," p. 3.]

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"The aluminous minerals contained in granite rocks are feldspar, mica, and hornblende. . . . Mica and hornblende generally contain considerable oxide of iron, while feldspar usually yields only a trace or none. Therefore clays which are derived from feldspar are light-colored or white, while those partially made up of decomposed mica or hornblende are dark, either bluish or red."[1]

The tail of the comet seems to be perpetually in motion. It is, says one writer, "continually changing and fluctuating as vaporous masses of cloud-like structure might be conceived to do, and in some instances there has been a strong appearance even of an undulating movement."[2]

The great comet of 1858, Donati's comet, which many now living will well remember, and which was of such size that when its head was near our horizon the extremity of the tail reached nearly to the zenith, illustrated this continual movement of the material of the tail; that appendage shrank and enlarged millions of miles in length.

Mr. Lockyer believed that he saw in Coggia's comet the evidences of a whirling motion—

"In which the regions of greatest brightness were caused by the different coils cutting, or appearing to cut, each other, and so in these parts leading to compression or condensation, and frequent collision of the luminous particles."

Olbers saw in a comet's tail—

"A sudden flash and pulsation of light which vibrated for several seconds through it, and the tail appeared during the continuance of the pulsations of light to be lengthened by several degrees and then again contracted."[1]

[1. "American Cyclopdia," article "Clay."

2. "Edinburgh Review," October, 1874, p. 208,

3, "Cosmos," vol. i, p. 143.]

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Now, in this perpetual motion, this conflict, these great thrills of movement, we are to find the source of the clays which cover a large part of our globe to a depth of hundreds of feet. Where are those exposures of granite on the face of the earth from which ice or water could have ground them? Granite, I repeat, comes to the surface only in limited areas. And it must be remembered that clay is the product exclusively of granite ground to powder. The clays are composed exclusively of the products of disintegrated granite. They contain but a trace of lime or magnesia or organic matters, and these can be supposed to have been infiltrated into them after their arrival on the face of the earth.[1] Other kinds of rock, ground up, form sand. Moreover, we have seen that neither glaciers nor ice-sheets now produce such clays.

We shall see, as we proceed, that the legends of mankind, in describing the comet that struck the earth, represent it as party-colored; it is "speckled" in one legend; spotted like a tiger in another; sometimes it is a white boar in the heavens; sometimes a blue snake; sometimes it is red with the blood of the millions that are to perish. Doubtless these separate formations, ground out of the granite, from the mica, hornblende, or feldspar, respectively, may, as I have said, under great laws, acted upon by magnetism or electricity, have arranged themselves in separate lines or sheets, in the tail of the comet, and hence we find that the clays of one region are of one color, while those of another are of a different hue. Again, we shall see that the legends represent the monster as "winding," undulating, writhing, twisting, fold over fold, precisely as the telescopes show us the comets do to-day.

[1. "American Cyclopdia," vol. iv, p. 650.]

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The very fact that these waves of motion run through the tail of the comet, and that it is capable of expanding and contracting on an immense scale, is conclusive proof that it is composed of small, adjustable particles. The writer from whom I have already quoted, speaking of the extraordinary comet of 1843, says:

"As the comet moves past the great luminary, it sweeps round its tail as a sword may be conceived to be held out at arm's-length, and then waved round the head, from one side to the opposite. But a sword with a blade one hundred and fifty millions of miles long must be a somewhat awkward weapon to brandish round after this fashion. Its point would have to sweep through a curve stretching out more than six hundred millions of miles; and, even with an allowance of two hours for the accomplishment of the movement, the flash of the weapon would be of such terrific velocity that it is not an easy task to conceive how any blade of connected material substance could bear the strain of the stroke. Even with a blade that possessed the coherence and tenacity of iron or steel, the case would be one that it would be difficult for molecular cohesion to deal with. But that difficulty is almost infinitely increased when it is a substance of much lower cohesive tenacity than either iron or steel that has to be subjected to the strain.

"There would be, at least, some mitigation of this difficulty if it were lawful to assume that the substance which is subjected to this strain was not amenable to the laws of ponderable existence; if there were room for the notion that comets and their tails, which have to be brandished in such a stupendous fashion, were sky-spectres, immaterial phantoms, unreal visions of that negative shadow-kind which has been alluded to. This, however, unfortunately, is not a permissible alternative in the circumstances of the case. The great underlying and indispensable fact that the comet comes rushing up toward the sun out of space, and then shoots round that great center of attraction by the force of its own acquired and ever-increasing impetuosity; the fact that it is obedient

{p. 78}

through this course to the law of elliptical, or, to speak more exactly, of conic-section, movement, permits of no doubt as to the condition of materiality. The comet is obviously drawn by the influence of the sun's mass, and is subservient to that all-pervading law of sympathetic gravitation that is the sustaining bond of the material universe. It is ponderable substance beyond all question, and held by that chain of physical connection which it was the glory of Newton to discover. If the comet were not a material and ponderable substance it would not gravitate round the sun, and it would not move with increasing velocity as it neared the mighty mass until it had gathered the energy for its own escape in the enhanced and quickened momentum. In the first instance, the ready obedience to the attraction, and then the overshooting of the spot from which it is exerted, combine to establish the comet's right to stand ranked at least among the ponderable bodies of space."[1]

And it is to the comet we must look for the source of a great part of those vast deposits of gravel which go to constitute the Drift.

"They have been usually attributed to the action of waves; but the mechanical work of the ocean is mostly confined to its shores and soundings, where alone material exists in quantity within reach of the waves and currents.[2] . . . The eroding action is greatest for a short distance above the height of half-tide, and, except in violent storms, it is almost null below low-tide."[3]

But if any one will examine a sea-beach he will see, not a vast mass of pebbles perpetually rolling and grinding each other, but an expanse of sand. And this is to be expected; for as soon as a part of the pebbles is, by the attrition of the waves, reduced to sand, the sand packs around the stones and arrests their further waste. To form such a mass of gravel as is found in the Drift we

[1. "Edinburgh Review," October, 1874, p. 202.

2. Dana's "Text Book," p. 286.

3. Ibid., p. 287.]

{p. 79}

must conceive of some way whereby, as soon as the sand is formed, it is removed from the stones while the work of attrition goes on. This process we can conceive of in a comet, if the finer detritus is constantly carried back and arranged in the order of the size of its particles.

To illustrate my meaning: let one place any hard substance, consisting of large fragments, in a mortar, and proceed to reduce it with a pestle to a fine powder. The work proceeds rapidly at first, until a portion of the material is triturated; you then find that the pulverized part has packed around and protected the larger fragments, and the work is brought to a stand-still. You have to remove the finer material if you would crush the pieces that remain.

The sea does not separate the sand from the gravel; it places all together at elevations where the waves can not reach them:

"Waves or shallow soundings have some transporting power; and, as they always move toward the land, their action is landward. They thus beat back, little by little, any detritus in the waters, preventing that loss to continents or islands which would take place if it were carried out to sea."[1]

The pebbles and gravel are soon driven by the waves up the shore, and beyond the reach of further wear;[2] and "the rivers carry only silt to the ocean."[3]

The brooks and rivers produce much more gravel than the sea-shore:

"The detritus brought down by rivers is vastly greater in quantity than the stones, sand, or clay produced by the wear of the coasts."[4]

[1. Dana's "Text Book," p. 288.

2. Ibid., p. 291.

3. Ibid., p. 302.

4. Ibid., p. 290.]

{p. 80}

But it would be absurd to suppose that the beds of rivers could have furnished the immeasurable volumes of gravel found over a great part of the world in the drift-deposits.

And the drift-gravel is different from the gravel of the sea or rivers.

Geikie says, speaking of the "till":

"There is something very peculiar about the shape of the stones. They are neither round and oval, like the pebbles in river-gravel, or the shingle of the sea-shore, nor are they sharply angular like newly-fallen dbris at the base of a cliff, although they more closely resemble the latter than the former. They are, indeed, angular in shape, but the sharp corners and edges have invariably been smoothed away. . . . Their shape, as will be seen, is by no means their most striking peculiarity. Each is smoothed, polished, and covered with stri or scratches, some of which are delicate as the lines traced by an etching-needle, others deep and harsh as the scores made by the plow upon a rock. And, what is worthy of note, most of the scratches, coarse and fine together, seem to run parallel to the longer diameter of the stones, which, however, are scratched in many other directions as well."[1]

Let me again summarize:

I. Comets consist of a blazing nucleus and a mass of ponderable, separated matter, such as stones, gravel, clay-dust, and gas.

II. The nucleus gives out great heat and masses of burning gas.

III. Luminous gases surround the nucleus.

IV. The drift-clays are the result of the grinding up of granitic rocks.

V. No such deposits, of anything like equal magnitude, could have been formed on the earth.

[1. "The Great Ice Age," p. 13.]

{p. 81}

VI. No such clays are now being formed under glaciers or Arctic ice-sheets.

VII. These clays were ground out of the substance of the comet by the endless changes of position of the material of which it is composed as it flew through space, during its incalculable journeys in the long reaches of time.

VIII. The earth-supplies of gravel are inadequate to account for the gravel of the drift-deposits.

IX. Neither sea-beach nor rivers produce stones like those found in the Drift.

I pass now to the next question.

{p. 82}

CHAPTER III.

COULD A COMET STRIKE THE EARTH?

READER, the evidence I am about to present will satisfy you, not only that a comet might have struck the earth in the remote past, but, that the marvel is that the earth escapes collision for a single century, I had almost said for a single year.

How many comets do you suppose there are within the limits of the solar system (and remember that the solar system occupies but an insignificant portion of universal space)?

Half a dozen-fifty-a hundred-you will answer.

Let us put the astronomers on the witness-stand:

Kepler affirmed that "COMETS ARE SCATTERED THROUGH THE HEAVENS WITH AS MUCH PROFUSION AS FISHES IN THE OCEAN."

Think of that!

"Three or four telescopic comets are now entered upon astronomical records every year. Lalande had a list of seven hundred comets that had been observed in his time."

Arago estimated that the comets belonging to the solar system, within the orbit of Neptune, numbered seventeen million five hundred thousand!

Lambert regards five hundred millions as a very moderate estimate![1]

[1. Guillemin, "The Heavens," p. 251.]

{p. 83}

And this does not include the monstrous fiery wanderers who may come to visit us, bringing their relations

#

ORBITS OF THE PERIODIC COMETS.

along, from outside the solar system—a sort of celestial immigrants whom no anti-Chinese legislation can keep away.

Says Guillemin:

"Leaving mere re-appearances out of the question, new comets are constantly found to arrive from the depths of space, describing around the sun orbits which testify to the attractive power of that radiant body; and, for the

{p. 84}

most part, going away for centuries, to return again from afar after their immense revolutions."[1]

But do these comets come anywhere near the orbit of the earth?

Look at the map on the preceding page, from Amde Guillemin's great work, "The Heavens," page 244, and you can answer the question for yourself.

Here you see the orbit of the earth overwhelmed in a complication of comet-orbits. The earth, here, is like a lost child in the midst of a forest full of wild beasts.

And this diagram represents the orbits of only six comets out of those seventeen millions or five hundred millions!

It is a celestial game of ten-pins, with the solar system for a bowling-alley, and the earth waiting for a ten-strike.

In 1832 the earth and Biela's comet, as I will show more particularly hereafter, were both making for the same spot, moving with celestial rapidity, but the comet reached the point of junction one month before the earth did; and, as the comet was not polite enough to wait for us to come up, this generation missed a revelation.

"In the year 1779 Lexell's comet approached so near to the earth that it would have increased the length of the sidereal year by three hours if its mass had been equal to the earth's."[2]

And this same comet did strike our fellow-planet, Jupiter.

[1. "The Heavens," p. 251.

2. "Edinburgh Review," October, 1874, p. 205.]

{p. 85}

In the years 1767 and 1779 Lexell's comet passed though the midst of Jupiter's satellites, and became entangled temporarily among them. But not one of the satellites altered its movements to the extent of a hair's breadth, or of a tenth of an instant."[1]

But it must be remembered that we had no glasses then, and have none now, that could tell us what were the effects of this visitation upon the surface of Jupiter or its moons. The comet might have covered Jupiter one hundred feet—yes, one hundred miles—thick with gravel and clay, and formed clouds of its seas five miles in thickness, without our knowing anything about it. Even our best telescopes can only perceive on the moon's surface—which is, comparatively speaking, but a few miles distant from us—objects of very great size, while Jupiter is sixteen hundred times farther away from us than the moon.

But it is known that Lexell's comet was very much demoralized by Jupiter. It first came within the influence of that planet in 1767; it lost its original orbit, and went bobbing around Jupiter until 1779, when it became entangled with Jupiter's moons, and then it lost its orbit again, and was whisked off into infinite space, never more, perhaps, to be seen by human eyes. Is it not reasonable to suppose that an event which thus demoralized the comet may have caused it to cast down a considerable part of its material on the face of Jupiter?

Encke's comet revolves around the sun in the short period of twelve hundred and five days, and, strange to say—

"The period of its revolution is constantly diminishing; so that, if this progressive diminution always follows the same rate, the time when the comet, continually

[1. "Edinburgh Review," October, 1874, p. 205.]

{p. 86}

describing a spiral, will be plunged into the incandescent mass of the sun can be calculated."[1]

The comet of 1874, first seen by Coggia, at Marseilles, and called by his name, came between the earth and the sun, and approached within sixty thousand miles of the flaming surface of the sun. It traveled through this fierce blaze at the rate of three hundred and sixty-six miles per second! Three hundred and sixty-six miles per second! When a railroad-train moves at the rate of a mile per minute, we regard it as extraordinary speed; but three hundred and sixty-six miles per second! The mind fails to grasp it.

When this comet was seen by Sir John Herschel, after it had made its grand sweep around the sun, it was not more than six times the breadth of the sun's face away from the sun. And it had come careering through infinite space with awful velocity to this close approximation to our great luminary.

And remember that these comets are no animalcul. They are monsters that would reach from the sun to the earth. And when we say that they come so close to the sun as in the above instances, it means peril to the earth by direct contact; to say nothing of the results to our planet by the increased combustion of the run, and the increased heat on earth should one of them fall upon the sun. We have seen, in the last chapter, that the great comet of 1843 possessed a tail one hundred and fifty million miles long; that is, it would reach from the sun to the earth, and have over fifty million miles of tail to spare; and it swept this gigantic appendage around in two hours, describing the are of a circle six hundred million miles long!

[1. Guillemin, "The Heavens," p. 247.]

{p. 87}

The mind fails to grasp these figures. Solar space is hardly large enough for such gyrations.

And it must be remembered that this enormous creature actually grazed the surface of the sun.

And it is supposed that this monster of 1843, which was first seen in 1668, returned, and was seen in the southern hemisphere in 1880—that is to say, it came back in thirty-seven years instead of one hundred and seventy-five years. Whereupon Mr. Proctor remarked:

"If already the comet experiences such resistance in passing through the corona when at its nearest to the sun that its period undergoes a marked diminution, the effect must of necessity be increased at each return, and after only a few, possibly one or two, circuits, the comet will be absorbed by the sun."

On October 10, 1880, Lewis Swift, of Rochester, New York, discovered a comet which has proved to be of peculiar interest. From its first discovery it has presented no brilliancy of appearance, for, during its period of visibility, a telescope of considerable power was necessary to observe it. Since this comet, when in close proximity to the earth, was very faint indeed, its dimensions must be quite moderate.

The illustration on page 88 gives the orbit of the earth and the orbit of this comet, and shows how closely they approached each other; when at its nearest, the comet was only distant from the earth 0.13 of the distance of the earth from the sun.

It comes back in eleven years, or in 1891.

On the 22d of June, 1881, a comet of great brilliancy flashed suddenly into view. It was unexpected, and advanced with tremendous rapidity. The illustration on page 89 will show how its flight intersected the orbit of the earth. At its nearest point, June 19th, it was distant

{p. 88}

from the earth only 0.28 of the distance of the sun from the earth.

Now, it is to be remembered that great attention has been paid during the past few years to searching for comets, and some of the results are here given. As many as five were discovered during the year 1881. But not

#

ORBIT OF EARTH AND COMET

a few of the greatest of these strange orbs require thousands of years to complete their orbits. The period of the comet of July, 1844, has been estimated at not less than one hundred thousand years!

Some of those that have flashed into sight recently have been comparatively small, and their contact with

{p. 89}

#

THE EARTH'S ORBIT

the earth might produce but trifling results. Others, again, are constructed on an extraordinary scale; but even the largest of these may be but children compared with the monsters that wander through space on orbits

{p. 90}

that penetrate the remotest regions of the solar system, and even beyond it.

When we consider the millions of comets around us, and when we remember how near some of these have come to us during the last few years, who will undertake to say that during the last thirty thousand, fifty thousand, or one hundred thousand years, one of these erratic luminaries, with blazing front and train of dbris, may not have come in collision with the earth?

{p. 91}

CHAPTER IV.

THE CONSEQUENCES TO THE EARTH.

IN this chapter I shall try to show what effect the contact of a comet must have had upon the earth and its inhabitants.

I shall ask the reader to follow the argument closely first, that he may see whether any part of the theory is inconsistent with the well-established principles of natural philosophy; and, secondly, that he may bear the several steps in his memory, as he will find, as we proceed, that every detail of the mighty catastrophe has been preserved in the legends of mankind, and precisely in the order in which reason tells us they must have occurred.

In the first place, it is, of course, impossible at this time to say precisely how the contact took place; whether the head of the comet fell into or approached close to the sun, like the comet of 1843, and then swung its mighty tail, hundreds of millions of miles in length, moving at a rate almost equal to the velocity of light, around through a great are, and swept past the earth;—the earth, as it were, going through the midst of the tail, which would extend for a vast distance beyond and around it. In this movement, the side of the earth, facing the advance of the tail, would receive and intercept the mass of material—stones, gravel, and the finely-ground-up-dust which, compacted by water, is now clay—which came in contact with it, while the comet would sail off into space,

{p. 92}

demoralized, perhaps, in its orbit, like Lexell's comet when it became entangled with Jupiter's moons, but shorn of a comparatively small portion of its substance.

The following engraving will illustrate my meaning. I can not give, even approximately, the proportions of the

#

THE COMET SWEEPING PAST THE EARTH.

objects represented, and thus show the immensity of the sun as compared with our insignificant little orb. In a picture showing the true proportions of the sun and earth, the sun would have to be so large that it would take up the entire page, while the earth would be but as a

{p. 93}

#

THE SIDE OF THE EARTH STRUCK BY THE COMET {left}

THE SIDE NOT STRUCK BY THE COMET {right}

{p. 94}

pin-head. And I have not drawn the comet on a scale large enough as compared with the earth.

If the reader will examine the map on page 93, he will see that the distribution of the Drift accords with this theory. If we suppose the side of the earth shown in the left-hand figure was presented to the comet, we will see why the Drift is supposed to be confined to Europe, Africa, and parts of America; while the right-hand figure will show the half of the world that escaped.

"The breadth of the tail of the great comet of 1811, at its widest part, was nearly fourteen million miles, the length one hundred and sixteen million miles, and that of the second comet of the same year, one hundred and forty million miles."[1]

On page 95 is a representation of this monster.

Imagine such a creature as that, with a head fifty times as large as the moon, and a tail one hundred and sixteen million miles long, rushing past this poor little earth of ours, with its diameter of only seven thousand nine hundred and twenty-five miles! The earth, seven thousand nine hundred and twenty-five miles wide, would simply make a bullet-hole through that tail, fourteen million miles broad, where it passed through it!—a mere eyelet-hole—a pin-hole—closed up at once by the constant movements which take place in the tail of the comet. And yet in that moment of contact the side of the earth facing the comet might be covered with hundreds of feet of dbris.

Or, on the other hand, the comet may, as described in some of the legends, have struck the earth, head on, amid-ships, and the shock may have changed the angle of inclination of the earth's axis, and thus have modified

[1. Schellen, "Spectrum Analysis," p. 392.]

{p. 95}

permanently the climate of our globe; and to this cause we might look also for the great cracks and breaks in the earth's surface, which constitute the fiords of the sea-coast and the trap-extrusions of the continents; and here, too,

#

THE GREAT COMET OF 1811.

might be the cause of those mighty excavations, hundreds of feet deep, in which are now the Great Lakes of America, and from which, as we have seen, great cracks radiate out in all directions, like the fractures in a pane of glass where a stone has struck it.

The cavities in which rest the Great Lakes have been attributed to the ice-sheet, but it is difficult to comprehend how an ice-sheet could dig out and root out a hole, as in the case of Lake Superior, nine hundred feet deep!

{p. 96}

And, if it did this, why were not similar holes excavated wherever there were ice-sheets—to wit, all over the northern and southern portions of the globe? Why should a general cause produce only local results?

Sir Charles Lyell shows[1] that glaciers do not cut out holes like the depressions in which the Great Lakes lie; he also shows that these lakes are not due to a sinking down of the crust of the earth, because the strata are continuous and unbroken beneath them. He also calls attention to the fact that there is a continuous belt of such lakes, reaching from the northwestern part of the United States, through the Hudson Bay Territory, Canada, and Maine, to Finland, and that this belt does not reach below 50 north latitude in Europe and 40 in America. Do these lie in the track of the great collision? The comet, as the stri indicate, came from the north.

The mass of Donati's comet was estimated by MM. Faye and Roche at about the seven-hundredth part of the bulk of the earth. M. Faye says:

"That is the weight of a sea of forty thousand square miles one hundred and nine yards deep; and it must be owned that a like mass, animated with considerable velocity, might well produce, by its shock with the earth, very perceptible results."[2]

We have but to suppose, (a not unreasonable supposition,) that the comet which struck the earth was much larger than Donati's comet, and we have the means of accounting for results as prodigious as those referred to.

We have seen that it is difficult to suppose that ice produced the drift-deposits, because they are not found where ice certainly was, and they are found where ice certainly was not. But, if the reader will turn to the

[1. "Elements of Geology," pp. 168,171, et seq.

2. "The Heavens," p. 260.]

{p. 97}

illustration which constitutes the frontispiece of this volume, and the foregoing engraving on page 93, he will see that the Drift is deposited on the earth, as it might have been if it had suddenly fallen from the heavens; that is, it is on one side of the globe—to wit, the side that faced the comet as it came on. I think this map is substantially accurate. There is, however, an absence of authorities as to the details of the drift-distribution. But, if my theory is correct, the Drift probably fell at once. If it had been twenty-four hours in falling, the diurnal revolution would, in turn, have presented all sides of the earth to it, and the Drift would be found everywhere. And this is in accordance with what we know of the rapid movements of comets. They travel, as I have shown, at the rate of three hundred and sixty-six miles per second; this is equal to twenty-one thousand six hundred miles per minute, and one million two hundred and ninety-six thousand miles per hour!

And this accords with what we know of the deposition of the Drift. It came with terrific force. It smashed the rocks; it tore them up; it rolled them over on one another; it drove its material into the underlying rocks; "it indented it into them," says one authority, already quoted.

It was accompanied by inconceivable winds—the hurricanes and cyclones spoken of in many of the legends. Hence we find the loose material of the original surface gathered up and carried into the drift-material proper; hence the Drift is whirled about in the wildest confusion. Hence it fell on the earth like a great snow-storm driven by the wind. It drifted into all hollows; it was not so thick on, or it was entirely absent from, the tops of hills; it formed tails, precisely as snow does, on the leeward side of all obstructions. Glacier-ice is slow and plastic,

{p. 98}

and folds around such impediments, and wears them away; the wind does not. Compare the following representation of a well-known feature of the Drift, called

#

CRAG AND TAIL.—c, crag; t, till.

"crag and tail," taken from Geikie's work,[1] with the drifts formed by snow on the leeward side of fences or houses.

The material runs in streaks, just as if blown by violent winds:

"When cut through by rivers, or denuded by the action of the sea, ridges of bowlders are often seen to be inclosed within it. Although destitute of stratification, horizontal lines are found, indicating differences in texture and color."[2]

Geikie, describing the bowlder-clay, says:

"It seems to have come from regions whence it is bard to see how they could have been borne by glaciers. As a rule it is quite unstratified, but traces of bedding are not uncommon."

"Sometimes it contains worn fossils, and fragments of shells, broken, crushed, and striated; sometimes it contains bands of stones arranged in lines."

In short, it appears as if it were gusts and great whirls of the same material as the "till," lifted up by the cyclones and mingled with blocks, rocks, bones, sands, fossils, earth, peat, and other matters, picked up with terrible

[1. "The Great Ice Age," p. 18.

2. "American Cyclopdia," vol. vi, p. 112.]

{p. 99}

force from the face of the earth and poured down pell-mell on top of the first deposit of true "till."

In England ninety-four per cent of these stones found in this bowlder-clay are "stranger" stones; that is to say, they do not belong to the drainage area in which they are found, but must have been carried there from great distances.

But how about the markings, the stri, on the face of the surface-rocks below the Drift? The answer is plain. Dbris, moving at the rate of a million miles an hour, would produce just such markings.

Dana says:

"The sands carried by the winds when passing over rocks sometimes wear them smooth, or cover them with scratches and furrows, as observed by W. P. Blake on granite rocks at the Pass of San Bernardino, in California. Even quartz was polished and garnets were left projecting upon pedicels of feldspar. Limestone was so much worn as to look as if the surface had been removed by solution. Similar effects have been observed by Winchell in the Grand Traverse region, Michigan. Glass in the windows of houses on Cape Cod sometimes has holes worn through it by the same means. The hint from nature has led to the use of sand, driven by a blast, with or without steam, for cutting and engraving glass, and even for cutting and carving granite and other hard rocks."[1]

Gratacap describes the rock underneath the "till" as polished and oftentimes lustrous."[2]

But, it may be said, if it be true that dbris, driven by a terrible force, could have scratched and dented the rocks, could it have made long, continuous lines and grooves upon them? But the fact is, the stri on the face of the rocks covered by the Drift are not continuous;

[1. Dana's "Text-Book," p. 275.

2. "Popular Science Monthly," January, 1878, p. 320.]

{p. 100}

they do not indicate a steady and constant pressure, such as would result where a mountainous mass of ice had caught a rock and held it, as it were, in its mighty hand, and, thus holding it steadily, had scored the rocks with it as it moved forward.

"The groove is of irregular depth, its floor rising and falling, as though hitches had occurred when it was first planed, the great chisel meeting resistance, or being thrown up at points along its path."[1]

What other results would follow at once from contact with the comet?

We have seen that, to produce the phenomena of the Glacial age, it was absolutely necessary that it must have been preceded by a period of heat, great enough to vaporize all the streams and lakes and a large part of the ocean. And we have seen that no mere ice-hypothesis gives us any clew to the cause of this.

Would the comet furnish us with such heat? Let me call another witness to the stand:

In the great work of Amde Guillemin, already cited, we read:

"On the other hand, it seems proved that the light of the comets is, in part, at least, borrowed from the sun. But may they not also possess a light of their own? And, on this last hypothesis, is this brightness owing to a kind of phosphorescence, or to the state of incandescence of the nucleus? Truly, if the nuclei of comets be incandescent, the smallness of their mass would eliminate from the danger of their contact with the earth only one element of destruction: the temperature of the terrestrial atmosphere would be raised to an elevation inimical to the existence of organized beings; and we should only escape the danger of a mechanical shock, to run into a not less frightful

[1. Gratacap, "The Ice Age," in "Popular Science Monthly," January, 1818, p. 321.]

{p. 101}

one of being calcined in a many days passage through an immense furnace."[1]

Here we have a good deal more heat than is necessary to account for that vaporization of the seas of the globe which seems to have taken place during the Drift Age.

But similar effects might be produced, in another way, even though the heat of the comet itself was inconsiderable.

Suppose the comet, or a large part of it, to have fallen into the sun. The arrested motion would be converted into heat. The material would feed the combustion of the sun. Some have theorized that the sun is maintained by the fall of cometic matter into it. What would be the result?

Mr. Proctor notes that in 1866 a star, in the constellation Northern Cross, suddenly shone with eight hundred times its former luster, afterward rapidly diminishing in luster. In 1876 a new star in the constellation Cygnus became visible, subsequently fading again so as to be only perceptible by means of a telescope; the luster of this star must have increased from five hundred to many thousand times.

Mr. Proctor claims that should our sun similarly increase in luster even one hundred-fold, the glowing heat would destroy all vegetable and animal life on earth.

There is no difficulty in seeing our way to heat enough, if we concede that a comet really struck the earth or fell into the sun. The trouble is in the other direction—we would have too much heat.

We shall see, hereafter, that there is evidence in our rocks that in two different ages of the world, millions of years before the Drift period, the whole surface of the

[1. "The Heavens," p. 260.]

{p. 102}

earth was actually fused and melted, probably by cometic contact.

This earth of ours is really a great powder-magazine there is enough inflammable and explosive material about it to blow it into shreds at any moment.

Sir Charles Lyell quotes, approvingly, the thought of Pliny: "It is an amazement that our world, so full of combustible elements, stands a moment unexploded."

It needs but an infinitesimal increase in the quantity of oxygen in the air to produce a combustion which would melt all things. In pure oxygen, steel burns like a candle-wick. Nay, it is not necessary to increase the amount of oxygen in the air to produce terrible results. It has been shown[1] that, of our forty-five miles of atmosphere, one fifth, or a stratum of nine miles in thickness, is oxygen. A shock, or an electrical or other convulsion, which would even partially disarrange or decompose this combination, and send an increased quantity of oxygen, the heavier gas, to the earth, would wrap everything in flames. Or the same effects might follow from any great change in the constitution of the water of the world. Water is composed of eight parts of oxygen and one part of hydrogen. "The intensest heat by far ever yet produced by the blow-pipe is by the combustion of these two gases." And Dr. Robert Hare, of Philadelphia, found that the combination which produced the intensest heat was that in which the two gases were in the precise proportions found in water.[2]

We may suppose that this vast heat, whether it came from the comet, or the increased action of the sun, preceded the fall of the dbris of the comet by a few minutes or a few hours. We have seen the surface-rocks

[1. "Science and Genesis," p. 125.

2. Ibid., p. 127.]

{p. 103}

described as lustrous. The heat may not have been great enough to melt them—it may merely have softened them; but when the mixture of clay, gravel, striated rocks, and earth-sweepings fell and rested on them, they were at once hardened and almost baked; and thus we can account for the fact that the "till," which lies next to the rocks, is so hard and tough, compared with the rest of the Drift, that it is impossible to blast it, and exceedingly difficult even to pick it to pieces; it is more feared by workmen and contractors than any of the true rocks.

Professor Hartt shows that there is evidence that some cause, prior to but closely connected with the Drift, did decompose the surface-rocks underneath the Drift to great depths, changing their chemical composition and appearance. Professor Hartt says:

"In Brazil, and in the United States in the vicinity of New York city, the surface-rocks, under the Drift, are decomposed from a depth of a few inches to that of a hundred feet. The feldspar has been converted into slate, and the mica has parted with its iron."[1]

Professor Hartt tries to account for this metamorphosis by supposing it to have been produced by warm rains! But why should there be warm rains at this particular period? And why, if warm rains occurred in all ages, were not all the earlier rocks similarly changed while they were at the surface?

Heusser and Clarez suppose this decomposition of the rocks to be due to nitric acid. But where did the nitric acid come from?

In short, here is the proof of the presence on the earth, just before the Drift struck it, of that conflagration which we shall find described in so many legends.

[1. "The Geology of Brazil," p. 25.]

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And certainly the presence of ice could not decompose rocks a hundred feet deep, and change their chemical constitution. Nothing but heat could do it.

But we have seen that the comet is self-luminous—that is, it is in process of combustion; it emits great gushes and spouts of luminous gases; its nucleus is enveloped in a cloak of gases. What effect would these gases have upon our atmosphere?

First, they would be destructive to animal life. But it does not follow that they would cover the whole earth. If they did, all life must have ceased. They may have fallen in places here and there, in great sheets or patches, and have caused, until they burned themselves out, the conflagrations which the traditions tell us accompanied the great disaster.

Secondly, by adding increased proportions to some of the elements of our atmosphere they may have helped to produce the marked difference between the pre-glacial and our present climate.

What did these gases consist of?

Here that great discovery, the spectroscope, comes to our aid. By it we are able to tell the elements that are being consumed in remote stars; by it we have learned that comets are in part self-luminous, and in part shine by the reflected light of the sun; by it we are even able to identify the very gases that are in a state of combustion in comets.

In Schellen's great work[1] I find a cut (see next page) comparing the spectra of carbon with the light emitted by two comets observed in 1868—Winnecke's comet and Brorsen's comet.

Here we see that the self-luminous parts of these comets

[1. "Spectrum Analysis," p. 396.]

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burned with substantially the same spectrum as that emitted by burning carbon. The inference is irresistible that these comets were wrapped in great masses of carbon in a state of combustion. This is the conclusion reached by Dr. Schellen.

#

SOLAR SPECTRUM

Padre Secchi, the great Roman astronomer, examined Dr. Winnecke's comet on the 21st of June, 1868, and concluded that the light from the self-luminous part was produced by carbureted hydrogen.

We shall see that the legends of the different races speak of the poison that accompanied the comet, and by which great multitudes were slain; the very waters that

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first flowed through the Drift, we are told, were poisonous. We have but to remember that carbureted hydrogen is the deadly fire-damp of the miners to realize what effect great gusts of it must have had on animal life.

We are told[1] that it burns with a yellow flame when subjected to great heat, and some of the legends, we will see hereafter, speak of the "yellow hair" of the comet that struck the earth.

And we are further told that, "when it, carbureted hydrogen, is mixed in due proportion with oxygen or atmospheric air, a compound is produced which explodes with the electric spark or the approach of flame." Another form of carbureted hydrogen, olefiant gas, is deadly to life, burns with a white light, and when mixed with three or four volumes of oxygen, or ten or twelve of air, it explodes with terrific violence.

We shall see, hereafter, that many of the legends tell us that, as the comet approached the earth, that is, as it entered our atmosphere and combined with it, it gave forth world-appalling noises, thunders beyond all earthly thunders, roarings, howlings, and hissings, that shook the globe. If a comet did come, surrounded by volumes of carbureted hydrogen, or carbon combined with hydrogen, the moment it reached far enough into our atmosphere to supply it with the requisite amount of oxygen or atmospheric air, precisely such dreadful explosions would occur, accompanied by noises similar to those described in the legends.

Let us go a step further:

Let us try to conceive the effects of the fall of the material of the comet upon the earth.

We have seen terrible rain-storms, hail-storms, snow-storms;

[1. "American Cyclopdia," vol. iii, p. 776.]

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but fancy a storm of stones and gravel and clay-dust!—not a mere shower either, but falling in black masses, darkening the heavens, vast enough to cover the world in many places hundreds of feet in thickness; leveling valleys, tearing away and grinding down hills, changing the whole aspect of the habitable globe. Without and above it roars the earthquaking voice of the terrible explosions; through the drifts of dbris glimpses are caught of the glaring and burning monster; while through all and over all is an unearthly heat, under which rivers, ponds, lakes, springs, disappear as if by magic.

Now, reader, try to grasp the meaning of all this description. Do not merely read the words. To read aright, upon any subject, you must read below the words, above the words, and take in all the relations that surround the words. So read this record.

Look out at the scene around you. Here are trees fifty feet high. Imagine an instantaneous descent of granite-sand and gravel sufficient to smash and crush these trees to the ground, to bury their trunks, and to cover the earth one hundred to five hundred feet higher than the elevation to which their tops now reach! And this not alone here in your garden, or over your farm, or over your township, or over your county, or over your State; but over the whole continent in which you dwell—in short, over the greater part of the habitable world!

Are there any words that can draw, even faintly, such a picture—its terror, its immensity, its horrors, its destructiveness, its surpassal of all earthly experience and imagination? And this human ant-hill, the world, how insignificant would it be in the grasp of such a catastrophe! Its laws, its temples, its libraries, its religions, its armies, its mighty nations, would be but as the veriest

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stubble—dried grass, leaves, rubbish-crushed, smashed, buried, under this heaven-rain of horrors.

But, lo! through the darkness, the wretches not beaten down and whelmed in the dbris, but scurrying to mountain-caves for refuge, have a new terror: the cry passes from lip to lip, "The world is on fire!"

The head of the comet sheds down fire. Its gases have fallen in great volumes on the earth; they ignite; amid the whirling and rushing of the dbris, caught in cyclones, rises the glare of a Titanic conflagration. The winds beat the rocks against the rocks; they pick up sand-heaps, peat-beds, and bowlders, and whirl them madly in the air. The heat increases. The rivers, the lakes, the ocean itself, evaporate.

And poor humanity! Burned, bruised, wild, crazed, stumbling, blown about like feathers in the hurricanes, smitten by mighty rocks, they perish by the million; a few only reach the shelter of the caverns; and thence, glaring backward, look out over the ruins of a destroyed world.

And not humanity alone has fled to these hiding-places: the terrified denizens of the forest, the domestic animals of the fields, with the instinct which in great tempests has driven them into the houses of men, follow the refugees into the caverns. We shall see all this depicted in the legends.

The first effect of the great heat is the vaporization of the waters of the earth; but this is arrested long before it has completed its work.

Still the heat is intense—how long it lasts, who shall tell? An Arabian legend indicates years.

The stones having ceased to fall, the few who have escaped—and they are few indeed, for many are shut up for ever by the clay-dust and gravel in their hiding-places,

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and on many others the convulsions of the earth have shaken down the rocky roofs of the caves—the few survivors come out, or dig their way out, to look upon a changed and blasted world. No cloud is in the sky, no rivers or lakes are on the earth; only the deep springs of the caverns are left; the sun, a ball of fire, glares in the bronze heavens. It is to this period that the Norse legend of Mimer's well, where Odin gave an eye for a drink of water, refers.

But gradually the heat begins to dissipate. This is a signal for tremendous electrical action. Condensation commences. Never has the air held such incalculable masses of moisture; never has heaven's artillery so rattled and roared since earth began! Condensation means clouds. We will find hereafter a whole body of legends about "the stealing of the clouds" and their restoration. The veil thickens. The sun's rays are shut out. It grows colder; more condensation follows. The heavens darken. Louder and louder bellows the thunder. We shall see the lightnings represented, in myth after myth, as the arrows of the rescuing demi-god who saves the world. The heat has carried up perhaps one fourth of all the water of the world into the air. Now it is condensed into cloud. We know how an ordinary storm darkens the heavens. In this case it is black night. A pall of dense cloud, many miles in thickness, enfolds the earth. No sun, no moon, no stars, can be seen. "Darkness is on the face of the deep." Day has ceased to be. Men stumble against each other. All this we shall find depicted in the legends. The overloaded atmosphere begins to discharge itself. The great work of restoring the waters of the ocean to the ocean begins. It grows colder—colder—colder. The pouring rain turns into snow, and settles on all the uplands and north countries; snow falls on

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snow; gigantic snow-beds are formed, which gradually solidify into ice. While no mile-thick ice-sheet descends to the Mediterranean or the Gulf of Mexico, glaciers intrude into all the valleys, and the flora and fauna of the temperate regions become arctic; that is to say, only those varieties of plants and animals survive in those regions that are able to stand the cold, and these we now call arctic.

In the midst of this darkness and cold and snow, the remnants of poor humanity wander over the face of the desolated world; stumbling, awe-struck, but filled with an insatiable hunger which drives them on; living upon the bark of the few trees that have escaped, or on the bodies of the animals that have perished, and even upon one another.

All this we shall find plainly depicted in the legends of mankind, as we proceed.

Steadily, steadily, steadily—for days, weeks, months, years—the rains and snows fall; and, as the clouds are drained, they become thinner and thinner, and the light increases.

It has now grown so light that the wanderers can mark the difference between night and day. "And the evening and the morning were the first day."

Day by day it grows lighter and warmer; the piled-up snows begin to melt. It is an age of tremendous floods. All the low-lying parts of the continents are covered with water. Brooks become mighty rivers, and rivers are floods; the Drift dbris is cut into by the waters, re-arranged, piled up in what is called the stratified, secondary, or Champlain drift. Enormous river-valleys are cut out of the gravel and clay.

The seeds and roots of trees and grasses, uncovered by the rushing torrents, and catching the increasing

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warmth, begin to put forth green leaves. The sad and parti-colored earth, covered with white, red, or blue clays and gravels, once more, wears a fringe of green.

The light increases. The warmth lifts up part of the water already cast down, and the outflow of the steaming ice-fields, and pours it down again in prodigious floods. It is an age of storms.

The people who have escaped gather together. They know the sun is coming back. They know this desolation is to pass away. They build great fires and make human sacrifices to bring back the sun. They point and guess where he will appear; for they have lost all knowledge of the cardinal points. And all this is told in the legends.

At last the great, the godlike, the resplendent luminary breaks through the clouds and looks again upon the wrecked earth.

Oh, what joy, beyond all words, comes upon those who see him! They fall upon their faces. They worship him whom the dread events have taught to recognize as the great god of life and light. They burn or cast down their animal gods of the pre-glacial time, and then begins that world-wide worship of the sun which has continued down to our own times.

And all this, too, we shall find told in the legends.

And from that day to this we live under the influence of the effects produced by the comet. The mild, eternal summer of the Tertiary age is gone. The battle between the sun and the ice-sheets continues. Every north wind brings us the breath of the snow; every south wind is part of the sun's contribution to undo the comet's work. A continual amelioration of climate has been going on since the Glacial age; and, if no new catastrophe falls on the earth, our remote posterity will yet see the last snow-bank

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of Greenland melted, and the climate of the Eocene reestablished in Spitzbergen.

"It has been suggested that the warmth of the Tertiary climate was simply the effect of the residual heat of a globe cooling from incandescence, but many facts disprove this. For example, the fossil plants found in our Lower Cretaceous rocks in Central North America indicate a temperate climate in latitude 35 to 40 in the Cretaceous age. The coal-flora, too, and the beds of coal, indicate a moist, equable, and warm but not hot climate in the Carboniferous age, millions of years before the Tertiary, and three thousand miles farther south than localities where magnolias, tulip-trees, and deciduous cypresses, grew in the latter age. Some learned and cautious geologists even assert that there have been several Ice periods, one as far back as the Devonian."[1]

The ice-fields and wild climate of the poles, and the cold which descends annually over Europe and North America, represent the residuum of the refrigeration caused by the evaporation due to the comet's heat, and the long absence of the sun during the age of darkness. Every visitation of a comet would, therefore, necessarily eventuate in a glacial age, which in time would entirely pass away. And our storms are bred of the conflict between the heat and cold of the different latitudes. Hence, it may be, that the Tertiary climate represented the true climate of the earth, undisturbed by comet catastrophes; a climate equable, mild, warm, stormless. Think what a world this would be without tempests, cyclones, ice, snow, or cold!

Let us turn now to the evidences that man dwelt on the earth during the Drift, and that he has preserved recollections of the comet to this day in his myths and legends.

[1. "Popular Science Monthly," July, 1876, p. 283.]

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PART III

The Legends

CHAPTER I.

THE NATURE OF MYTHS.

IN a primitive people the mind of one generation precisely repeats the minds of all former generations; the construction of the intellectual nature varies no more, from age to age, than the form of the body or the color of the skin; the generations feel the same emotions, and think the same thoughts, and use the same expressions. And this is to be expected, for the brain is as much a part of the inheritable, material organization as the color of the eyes or the shape of the nose.

The minds of men move automatically: no man thinks because he intends to think; he thinks, as he hungers and thirsts, under a great primal necessity; his thoughts come out from the inner depths of his being as the flower is developed by forces rising through the roots of the plant.

The female bird says to herself, "The time is propitious, and now, of my own free will, and under the operation of my individual judgment, I will lay a nestful of eggs and batch a brood of children." But it is unconscious that it is moved by a physical necessity, which has constrained all its ancestors from the beginning of time,

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and which will constrain all its posterity to the end of time; that its will is nothing more than an expression of age, development, sunlight, food, and "the skyey influences." If it were otherwise it would be in the power of a generation to arrest the life of a race.

All great thoughts are inspirations of God. They are part of the mechanism by which he advances the race; they are new varieties created out of old genera.

There come bursts of creative force in history, when great thoughts are born, and then again Brahma, as the Hindoos say, goes to sleep for ages.

But, when the fever of creation comes, the poet, the inventor, or the philosopher can no more arrest the development of his own thoughts than the female bird, by her will-power, can stop the growth of the ova within her, or arrest the fever in the blood which forces her to incubation.

The man who wrote the Shakespeare plays recognized this involuntary operation of even his own transcendent intellect, when he said:

"Our poesy is a gum which oozes From whence 'tis nourished."

It came as the Arabian tree distilled its "medicinal gum"; it was the mere expression of an internal force, as much beyond his control as the production of the gum was beyond the control of the tree.

But in primitive races mind repeats mind for thousands of years. If a tale is told at a million hearth-fires, the probabilities are small, indeed, that any innovation at one hearth-fire, however ingenious, will work its way into and modify the narration at all the rest. There is no printing-press to make the thoughts of one man the thoughts of thousands. While the innovator is modifying

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the tale, to his own satisfaction, to his immediate circle of hearers, the narrative is being repeated in its unchanged form at all the rest. The doctrine of chances is against innovation. The majority rules.

When, however, a marvelous tale is told to the new generation—to the little ones sitting around with open eyes and gaping mouths—they naturally ask, "Where did all this occur?" The narrator must satisfy this curiosity, and so he replies, "On yonder mountain-top," or "In yonder cave."

The story has come down without its geography, and a new geography is given it.

Again, an ancient word or name may have a signification in the language in which the story is told different from that which it possessed in the original dialect, and, in the effort to make the old fact and the new language harmonize, the story-teller is forced, gradually, to modify the narrative; and, as this lingual difficulty occurs at every fireside, at every telling, an ingenious explanation comes at last to be generally accepted, and the ancient myth remains dressed in a new suit of linguistic clothes.

But, as a rule, simple races repeat; they do not invent.

One hundred years ago the highest faith was placed in written history, while the utmost contempt was felt for all legends. Whatever had been written down was regarded as certainly true; whatever had not been written down was necessarily false.

We are reminded of that intellectual old brute, Dr. Samuel Johnson, trampling poor Macpherson under foot, like an enraged elephant, for daring to say that he had collected from the mountaineers of wild Scotland the poems of Ossian, and that they had been transmitted, from mouth to mouth, through ages. But the great epic of the son of Fingal will survive, part of the widening

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heritage of humanity, while Johnson is remembered only as a coarse-souled, ill-mannered incident in the development of the great English people.

But as time rolled on it was seen that the greater part of history was simply recorded legends, while all the rest represented the passions of factions, the hates of sects, or the servility and venality of historians. Men perceived that the common belief of antiquity, as expressed in universal tradition, was much more likely to be true than the written opinions of a few prejudiced individuals.