Chapter V: Section 1

To State the Plutonic Theory of the Schools.

1. That all matter existed, or was created in a primeval state of heat. One hypothesis is, that all matter of our system was concentrated in one heated ball as a central sun.

2. That planets are portions of this matter, thrown off by a rapid rotary motion of the sun. Properly named, this theory was the centro-centrifugal theory, now quite out of date. That this theory might be true, the sun must have turned upon its axis with a velocity sufficient not only to destroy gravitation at its surface, now twenty-seven times that of the Earth, but with a force capable of throwing Jupiter, fourteen hundred times the size of the Earth, out into space four hundred and seventy-five million of miles, and Neptune over two billion of miles. When we consider that our sun now turns on its axis only once in twenty-seven days, we conclude that a vivid imagination must have supplied the machinery necessary for such astounding results in the very face of forbidding facts. This theory made no provision for the encircling waters, sufficient to wrap the entire surface of the globe three miles deep, nor for the enveloping atmosphere. Gradually this ancient theory has been modulated into the Nebulous Theory.

3. The more popular teaching of today is, that matter existed in a highly heated state in the form of a diffused cloud. Steel, in his “Fourteen Weeks in Geology,” suggests that “From unknown causes, this cloud-matter began to revolve about a center or sun. This nucleus drew matter direct to itself from all parts of our system. Other portions revolving were thrown off, and formed new centers for planetary gathering, as they respectively took up their orbicular march about the sun. This fiery mist is supposed to have come together in a heated state. The planets, at least, have since been cooling, though as yet having but a thin crust.” To this theory of primeval heat, in some form, all our text books conform. A theory so long and so universally accepted might be supposed to have some solid facts upon which to rest. But really it has less to sustain it than had the Ptolemaic theory of Astronomy: that, at least, had observation in its favor, but this fails even here. It is a curious circumstance in this guess work of results, that whether heat is made to increase on an average one degree in fifty feet, as given by many geologists, or one degree in one hundred feet, as given by others, precisely the same results are reached, viz., fifty miles crust, and intensely heated matter beyond. This assumption is based upon the supposed fact that the internal heat traverses the rock by conduction. If this were true, then the degree of heat gained in any one hundred feet of rock, as you descend into the Earth’s crust, would be the approximate measurement of any other hundred feet in the same shaft; but the reverse of this is true. No two measurements seem to be alike. The miner, as a practical geologist, in this regard knows that this heat is generally caused by chemical action of the rock upon which you have let in air or water, or both. This heat is found to vary according to nature of the rock which you expose. If the rock is rich in pyrites of iron or lime, in any of its numerous forms, then disintegration is abundant and much heat is generated; but, on the other hand, where all disintegrating elements are wanting, there is no perceptible increase of heat.

4. The theory of the continued increase of heat, according to the ratio noticed as you sink a shaft a few hundred feet into the Earth’s crust, if it proves anything proves too much, and is therefore false. Experiments extensively made in the Virginia mines of Nevada, and particularly in the Foreman Shaft, show the increase to be very uneven; differing from one degree in twelve feet to one in two hundred feet. It even grows colder as you descend some kind of rock, a degree in one hundred feet. The degree of heat is always regulated and gauged by the rock you pass. If the rock will disintegrate readily, it gives out more heat; but if the rock may lie exposed in the sun and rain without disintegration, it throws out no heat in the shaft. Yet from experiments made in the Foreman Shaft, notwithstanding these varieties of rock, yet at the 2,100 foot level it is found that the average increase is one degree in twelve feet. At this rate, at twenty-five miles towards the center you would encounter heat above 4,300 deg. Fahr. Chemists will admit that, after due allowance for pressure at such a depth, yet the granite with all known substances would fuse at this heat. The Plutonic hypothesis makes the crust in Nevada less than twenty-five miles, perhaps the weakest on the continent.

Experiments in Mexico, upon this line of reasoning, would make the crust twice as thick. Now from a well established law in philosophy, a pressure upon liquid on the inside of a cylinder imparts its pressure to every part of the cylinder at the same time. A pressure capable of breaking the crust in any place should, at least, cause all the openings to emit lava at the same time. But this is not the historic action of volcanoes; one emits while another sleeps.

It is a historic fact observed within the present century, that a volcanic mountain rose up from a comparatively level plane in Mexico, in one night, to the height of 1,695 feet. On the assumption that lava comes from the center of the earth, why should not the above pressure have found the weaker crust, and Nevada have been the place of eruption instead of Mexico? and why should not the three hundred open vents of Earth have emitted lava at the same time? The theory will not bear philosophic tests.

The Russian report of the increase of heat is only one-fourth that given in Nevada. Who believes, therefore, that the crust there is four times as thick as in Nevada? The whole subject shows that the increase of heat in the shaft proves nothing as to the interior of Earth, and nothing as to the thickness of its crust.

5. To establish the Plutonic theory, it is at least necessary to demonstrate that the granite, which all hold to be the under rock, is the unstratified Plutonic foundation of all stratified rock. Recent facts have demonstrated that the granite is a sedimentary rock, or rock deposited in water. This being admitted, although contradicting the teachings of all the older text books, some writers, among them is Steel, in order to harmonize the Plutonic theory with these stubborn facts, have assumed that the primitive granite, which by the theory must have been trap or lava, has all been worn away by disintegration of water and ice, or both; and again, by water deposited as we now find it. But what was a white-hot globe of lava doing, while water and ice were tearing and grinding its lower crust to powdered sand? We have secondary granite, but its structure is very different from primitive granite. Besides containing hard pebbles and boulders of other stone, it is friable, and easily disintegrated under exposure. It is a bad theory that is driven to such unheard-of suppositions for its support. Nothing is more evident, if the granite is the under rock, and sedimentary, as represented and known to be, than that the Plutonic theory is completely without foundation.

6. The modern theory of metamorphic rock, occasioned by internal heat, is also false. This theory maintains that the granite, slates, and marble existed so near to the great body of internal heat that they must have been metamorphosed. Facts demonstrate that these rocks, as a rule, were never in heat equal to 700 deg. Fahr. Such a heat will readily disintegrate any of these formations. Any one can demonstrate this by melting a little lead upon a piece of slate, marble, or granite. The furnace is found to be the best general test of the origin of rock. Lava, having been in a melted state, will not disintegrate up to the melting point, but, as a rule, will readily melt at the white heat. Granite, the slates, marble, and rock in general, of a sedimentary formation, will disintegrate at a comparatively low heat, but they will not melt, except with alkaloids, or flux, and then only at a very high degree of heat. This test shows all the primitive rock, including injected seams, to have been formed in the sea, with no heat to change their structure since. There are a few exceptions to the rule of disintegration, as clay rock.

7. If the granite were not sedimentary, we could not account for the great quantity of sedimentary rock this side. Among the authors of our text books there seems to be a general vagueness concerning the origin of stratified rock, except in regard to coal, which all admit came out of the air. If we should assume that the granite was lava, but all the stratified rock since, until you reach the region of conglomerate, came from the air, how shall we account for the close similarity in appearance and structure of the gneiss and granite? Theory has piled thirty or forty miles of this sedimentary, stratified rock above the granite; whence did it come? Any openings in the granite would let up only lava. Whence the material for sediment? We shall, farther on, show that all primitive rock, like the coal, came from the gases of the atmosphere once enveloping this globe.

8. Our best scientists now readily unite with the keen sighted miner in accounting for this increase of heat as you pass down the shaft, on entirely different principles from those stated in the text books. Prof. Joseph Le Conte says that “Chemical action of air and water upon the rock, as you descend into the Earth’s crust, is undoubtedly the cause of the increase of heat.” Again he says, “This heat is regulated and gauged by the constituents of the rock that you pass.” Now admitting that the rock, as a rule, would show an average increase of heat down to the Carboniferous system, or even to the Devonian, yet there is rock enough beyond that contains so much less carbon, as to show such a decrease of heat that must more than counteract all the increase above. Whether we follow up the old hypothesis, with the laws regulating heat by conduction or chemical action, the theory is utterly without foundation. The late Prof. Norton, of the California State Normal, said in a lecture at Pacific Grove, in 1883, “Every living geologist that I know of in the world will admit, for he _knows_, that the granite was a sedimentary rock.” This sentiment of his speech being reported to Le Conte, he replied, “In this position Prof. Norton is undoubtedly right.” It is thus seen that the Plutonic theory in our text books is at variance with modern experiments, and is proved to be utterly false.

9. Volcanoes and geysers were formerly supposed to settle the question in favor of the old theory. The phenomena of both are such as to strongly argue against it. Most geysers are known to be caused by chemical action of rock. We instance those in Hot Spring Valley, Cal., near Lassen Buttes. No one, having noticed the various colored mud-pots and mounds of pulpy rock thrown up by these boiling cauldrons, can come to any other conclusion. A few geysers may be exceptions, having been caused by water trickling over heated rock in proximity to volcanoes. These prove nothing as to the center of the earth, until it can be established that this body of lava is in the center of the earth. A multitude of facts in connection with volcanic action demonstrate that lava does not proceed from a common center.

A few we will here give. (1.) Lava varies in color according to the color of the stratified rock found in the vicinity. Thus, between Reno and Wadsworth, Nevada, may be seen a red ledge of sedimentary rock. Close by are found quantities of red lava, being the same shade of red found in the sedimentary. Pieces of rock may be seen, one side showing the sedimentary strata, and the other partially melted. Lava everywhere, probably, is only sedimentary rock melted. (2.) Volcanic disturbances are local, which they could not be if they proceeded from a common center. (3.) The existence of great quantities of ashes, so light as to float on the surface of water, argues the consumption of some burning material, as of coal. Nothing of this would exist in matter that had primarily been collected in liquid, and had ever been in a fused state. Something must have been burning to produce the ashes. (4.) The fact of all the great upheavals of plateaus and mountains having been this side the Carboniferous system of deposit, where the burning material, sufficient to produce volcanic effect, was extracted from the air and laid down as rock, argues in favor of a power much nearer than force, generated from a primeval sea of lava. Burning coal as a source of heat, and steam as a power, are ample to account for every volcanic disturbance, however it may have been modified by electric forces.

10. Most geologists are dissatisfied with the fire theory, and are looking about for a revolution in the teaching of the science. Professor Norton said, “We are upon the eve of a perfect revolution in the science of geology.” Agassiz said, “The Plutonic theory loses ground as soon as brought to scientific tests.” Again he uttered with decided emphasis, “If the center of our earth were molten lava, as hot as represented, a crust of rock fifty miles thick would melt, and, in the space of a few hours, fall into the great sea.”

A teacher of geology in one of our large colleges, who had just finished a lecture upon the Plutonic theory, said, “I have given that theory because it is the teaching of all our text-books; but I do not believe it. Many facts now coming to light show that the Water theory is destined to come to the front.”

11. The fact that submarine volcanoes happen, without letting the ocean into the great sea of lava, shows that no such sea is there. But for the money and reputation invested in school books upon this defunct theory, it would have been, before this, consigned to the Plutonic hell of the Greeks, from whence, it is more than probable, it originated.

12. Many admitted facts are utterly inconsistent with this theory. We will stop to notice but two.

(1.) It is a generally admitted fact, that the entire land portions of the explored earth, including Greenland to the 80th parallel, were either in a tropical or semi-tropical climate, from the beginning of sedimentary rock, up to and far into the so-called Alluvium deposit, and even to the historic age. “The climate of England was warmer than any now known on the earth.” Sir Chas. Lyell stated, that the only exceptions breaking in upon this uniformly warm climate were temporary changes during the great glacial epochs. This uniform heat could not result from the present auxiliary motion of the earth, nor with any good reason can we assert that the internal fires ever modulated the surface climate so much as one degree. Scientists are a unit in affirming that, for the last four thousand years, there has been no perceptible influence from this cause, upon our climate. A rupture of the earth’s crust, and a change of pole three thousand miles, and a complete change of pole-pointing, resulting in our present alternating seasons, has probably happened within the “historic age,” and probably within five thousand years. This could not be upon the Plutonic basis. Our earth could not part, and swim off upon a globe of melted lava.

(2.) Diatoms are now known to have existed, coequal with the deposit of all stratified rock. This is a well verified fact, but utterly inconsistent with the Plutonic theory. Upon this theory, the early crust of Earth must have remained at a white heat. Water could not lie upon it at all. Hence, both deposits in water and animal life would be out of the question. The fact of both, to say nothing of the well established fact of the sedimentary nature of granite, must ever brand the theory as contradicting the plain facts of nature. These facts equally refute the more modern notion of metamorphism of rock. The very waves of the sea unite in a chorus with the rocks, “The Plutonic foundations of the earth’s crust exist only in the imagination of man.”