Kitabı oku: «The Atlantic Monthly, Volume 18, No. 106, August, 1866», sayfa 4

One Sunday morning Sel complained of a headache. There was an evening service that night, and we all went to church. Mother let Sel take the empty seat in the carryall beside her.

It was very dark when we started to come home. But Creston was a safe old Orthodox town, the roads were filled with returning church-goers like ourselves, and mother drove like a man. A darker night I think I have never seen. Literally, we could not see a hand before our eyes. We met a carriage on a narrow road, and the horses' heads touched, before either driver had seen the other.

Selphar had been quite silent during the drive. I leaned forward, looked closely into her face, and could dimly see through the darkness that her eyes were closed.

"Why!" she said at last, "see those gloves!"

"Where?"

"Down in the ditch; we passed them before I spoke. I see them on a blackberry-bush; they've got little brass buttons on the wrist."

Three rods past now, and we could not see our horse's head.

"Selphar," said my mother, quickly, "what is the matter with you?"

"If you please, ma'am, I don't know," replied the girl, hanging her head. "May I get out and bring 'em to you?"

Prince was reined up, and Sel got out. She went so far back, that, though we strained our eyes to do it, we could not see her. In about two minutes she came up, a pair of gentleman's gloves in her hand. They were rolled together, were of cloth so black that on a bright night it would never have been seen, and had small brass buttons at the wrist.

Mother took them without a word.

The story leaked out somehow, and spread all over town. It raised a great hue and cry. Four or five antediluvian ladies declared at once that we were nothing more nor less than a family of "them spirituous mediums," and seriously proposed to expel mother from the prayer-meeting. Masculine Creston did worse. It smiled a pitying smile, and pronounced the whole thing the fancy of "scared women-folks." I could endure with calmness any slander upon earth but that. I sent by the next mail for Winthrop, and stated the case to him in a condition of suppressed fury. He very politely bit back an incredulous smile, and said he should be very happy to see her perform. The answer was somewhat dubious. I accepted it in silent suspicion.

He came on Saturday noon. That afternoon we attended en masse one of those refined inquisitions commonly known as picnics, and Winthrop lost his pocket-knife. Selphar, of course, kept house at home.

When we returned, Winthrop made some careless reference to his loss in her presence, and thought no more of it. About half an hour after, we observed that she was washing the dishes with her eyes shut. The condition had not been upon her five minutes before she dropped the spoon suddenly into the water, and asked permission to go out to walk. She "saw Mr. Winthrop's knife somewhere under a stone, and wanted to get it." It was fully two miles to the picnic grounds, and nearly dark. Winthrop followed the girl, unknown to her, and kept her in sight. She went rapidly, and without the slightest hesitation or search, to an out-of-the-way gully down by the pond, where Winthrop afterwards remembered having gone to cut some willow-twigs for the girls, parted a thick cluster of bushes, lifted a large, loose stone under which the knife had rolled, and picked it up. She returned it to Winthrop, quietly, and hurried away about her work to avoid being thanked.

I observed that, after this incident, masculine Creston became more respectful.

Of several peculiarities in this development of the girl I made at the time careful memoranda, and the exactness of these can be relied upon.

1. She herself, so far from attempting to bring on these trance states, or taking any pride therein, was intensely troubled and mortified by them,—would run out of the room, if she felt them coming on in the presence of visitors.

2. They were apt to be preceded by severe headaches, but came often without any warning.

3. She never, in any instance, recalled anything that happened during the trance, after it was passed.

4. She was powerfully and unpleasantly affected by electricity from a battery, or acting in milder forms. She was also unable at any time to put her hands and arms into hot water; the effect was to paralyze them at once.

5. Space proved to be no impediment to her vision. She has been known to follow the acts, words, and expressions of countenance of members of the family hundreds of miles away, with accuracy; as was afterwards proved by comparing notes as to time.

6. The girl's eyes, after her trances became habitual, assumed, and always retained, the most singular expression I ever saw on any face. They were oblong and narrow, and set back in her head like the eyes of a snake. They were not—smile if you will, O practical and incredulous reader!—but they were not human eyes. The eyes of Elsie Venner are the only eyes I can think of as at all like them. The most horrible circumstance about them—a circumstance that always made me shudder, familiar as I was with it—was, that, though turned fully on you, they never looked at you. Something behind them or out of them did the seeing, not they.

7. She not only saw substance, but soul. She has repeatedly told me my thoughts when they were upon subjects to which she could not by any possibility have had the slightest clew.

8. We were never able to detect a shadow of deceit about her.

9. The clairvoyance never failed in any instance to be correct, so far as we were able to trace it.

As will be readily imagined, the girl became a useful member of the family. The lost valuables restored and the warnings against mischances given by her quite balanced her incapacity for peculiar kinds of work. This incapacity, however, rather increased than diminished, and, together with her fickle health, which also grew more unsettled, caused us a great deal of care. The Creston physician—who was a keen man in his way, for a country doctor—pronounced the case altogether undreamt of before in Horatio's philosophy, and kept constant notes of it. Some of these have, I believe, found their way into the medical journals.

After a while there came, like a thief in the night, that which I suppose was poor Selphar's one unconscious, golden mission in this world. It came on a quiet summer night, that ended a long trance of a week's continuance. Mother had gone out into the kitchen to give an order for breakfast. I heard a few eager words in Selphar's voice, and then the door shut quickly, and it was an hour before it was opened.

Then my mother came to me without a particle of color in lips or cheek, and drew me away alone, and told the secret to me.

Selphar had seen Aunt Alice.

We sat down and looked at one another. There was a singular pinched look about my mother's mouth.

"Sarah."

"Yes."

"She says"—and then she told me what she said. She had seen Alice Stuart in a Western town, seven hundred miles away. Among the living, she desired to be counted of the dead. And that was all.

My mother paced the room three times back and forth, her hands locked.

"Sarah." There was a chill in her voice—it had been such a gentle voice!—that froze me. "Sarah, the girl is an impostor."

"Mother!"

She paced the room, once more, three times, back and forth. "At any rate, she is a poor, self-deluded creature. How can she see, seven hundred miles away, a dead woman who has been an angel all these years? Think! an angel, Sarah! So much better than I, and I—I loved—"

Before or since, I never heard my mother speak like that. She broke off sharply, and froze back into her chilling voice.

"We will say nothing about this, if you please. I do not believe a word of it."

We said nothing about it, but Selphar did. The delusion, if delusion it were, clung to her, haunted her, pursued her, week after week. To rid her of it, or to silence her, was impossible. She added no new facts to her first statement, but insisted that the long-lost dead was yet alive, with a quiet pertinacity that it was simply impossible to ridicule, frighten, threaten, or cross-question out of her, Clara was so thoroughly alarmed that she would not have slept alone for any mortal—perhaps not for any immortal—considerations. Winthrop and I talked the matter over often and gravely when we were alone and in quiet places. Mother's lips were sealed. From the day when Sel made the first disclosure, she was never heard once to refer to the matter. A perceptible haughtiness crept into her manner towards the girl. She even talked of dismissing her; but repented it, and melted into momentary gentleness. I could have cried over her that night. I was beginning to understand what a pitiful struggle her life had become, and how utterly alone she must be in it. She would not believe—she knew not what. She could not doubt the girl. And with the conflict even her children could not intermeddle.

To understand the crisis into which she was brought, the reader must bear in mind our long habit of belief, not only in Selphar's personal honesty, but in the infallibility of her mysterious power. Indeed, it had almost ceased to be mysterious to us, from daily familiarity. We had come to regard it as the curious working of physical disease, had taken its results as a matter of course, and had ceased, in common with converted Creston, to doubt the girl's capacity for seeing anything that she chose to, at any place.

Thus a year wore on. My mother grew sleepless and pallid. She laughed often, in a nervous, shallow way, as unlike her as a butterfly is unlike a sunset; and her face settled into an habitual sharpness and hardness unutterably painful to me.

Once only I ventured to break into the silence of the haunting thought that she knew, and we knew, was never escaped by either. "Mother, it would do no harm for Winthrop to go out West, and—"

She interrupted me sternly: "Sarah, I had not thought you capable of such childish superstition. I wish that girl and her nonsense had never come into this house!"—turning sharply away, and out of the room.

Just what that year was to my mother, I suppose only God and she have ever known, or will know.

But it ended. It ended at last, as I had prayed every night and morning of it that it should end. Mother came into my room one night, locked the door behind her, and, walking over to the window, stood with her face turned from me.

"Sarah."

"Yes."

"Sarah."

But that was all for a little while. Then,—"Sick and in suffering, Sarah,—the girl—she may be right, God Almighty knows! Sick and in suffering, you see. I am going. I think, I—"

The voice broke and melted utterly. I stole away and left her alone.

Creston put on its spectacles and looked wise on learning, the next day, that Mrs. Dugald had taken the earliest morning train for the West, on sudden and important business. It was precisely what Creston expected, and just like the Dugalds for all the world,—gone to hunt up material for that genealogical book, or map, or tree, or something, that they thought nobody knew they were going to publish. O yes, Creston understood it perfectly.

Space forbids me to relate in detail the clews which Selphar had given as to the whereabouts of the wanderer. Her trances, just at this time, were somewhat scarce and fragmentary, and the information she had professed to give had come in snatches and very imperfectly,—the trance being apt to end suddenly at the moment when some important question was pending, and then, of course, all memory of what she had said, or was about to say, was gone. The names and appearance of persons and places necessary to the search had, however, been given with sufficient distinctness to serve as a guide in my mother's rather chimerical undertaking. I suppose ninety-nine persons out of a hundred would have thought her a candidate for the State Lunatic Asylum. Exactly what she herself expected, hoped, or feared, I think it doubtful if she knew. I confess to a condition of simple bewilderment, when she was fairly gone, and Clara and I were left alone with Selphar's ghostly eyes forever on us. One night I had to lock the poor thing into her garret-room before I could sleep.

Just three weeks from the day mother started for the West, the coach rattled up to the door, and two women, arm in arm, came slowly up the walk. The one, erect, royal, with her great steadfast eyes alight; the other, bent and worn, gray-haired and sallow and dumb, crawling feebly through the golden afternoon sunshine, as the ghost of a glorious life might crawl back to its grave.

Mother threw open the door, and stood there like a queen. "Children, your aunt has come home. She is too tired to talk just now. By and by she will be glad to see you."

We took her gently up stairs, into the room where the lilies were mouldering to dust, and laid her down upon the bed. She closed her eyes wearily, turned her face over to the wall, and said no word.

What was the story of those tired eyes I never asked, and I never knew. Once, as I passed the room, a quick picture showed through the open door. The two women lying with their arms about each other's neck, as they used to do when they were children together; and above them, still and watchful, the wounded Face that had waited there so many years for this.

One was speaking with weak sobs, and very low. It was Aunt Alice. I caught but two words,—"My husband."

But what that husband was remains unknown till the day when the grave shall give up its dead, and the secrets of hearts oppressed and sinned against and sorrowful shall be revealed.

She lingered weakly there, within the restful room, for seven days, and then one morning we found her with her eyes upon the thorn-crowned face, her own quite still and smiling.

A little funeral train wound away one night behind the church, and left her down among those red-cup mosses that opened in so few months again to cradle the sister who had loved her. Two words only, by mother's orders, marked the simple headstone,—

"Alice Browning."

I have given you facts. Explain them as you will. I do not attempt it, for the simple reason that I cannot.

A word must be said as to the fate of poor Sel, which was mournful enough. Her trances grew gradually more frequent and erratic, till she became so thoroughly diseased in mind and body as to be entirely unfitted for household work, and, in short, nothing but an encumbrance. We kept her, however, for the sake of charity, and should have done so, till her poor, tormented life wore itself out; but after the advent of a new servant, and my mother's death, she conceived the idea that she was a burden, cried over it a few weeks, and at last one bitter winter's night she disappeared. We did not give up all search for her for years, but nothing was ever heard from her. He, I hope, who permitted life to be such a terrible mystery to her, has cared for her somehow, and kindly, and well.

THE MINER

 
Down 'mid the tangled roots of things
That coil about the central fire,
I seek for that which giveth wings,
To stoop, not soar, to my desire.
 
 
Sometimes I hear, as 't were a sigh,
The sea's deep yearning far above.
"Thou hast the secret not," I cry,
"In deeper deeps is hid my Love."
 
 
They think I burrow from the sun,
In darkness, all alone and weak;
Such loss were gain if He were won.
For 't is the sun's own Sun I seek.
 
 
The earth, they murmur, is the tomb
That vainly sought his life to prison;
Why grovel longer in its gloom?
He is not here; He hath arisen.
 
 
More life for me where He hath lain
Hidden, while ye believed him dead,
Than in cathedrals cold and vain,
Built on loose sands of "It is said."
 
 
My search is for the living gold,
Him I desire who dwells recluse,
And not his image, worn and old,
Day-servant of our sordid use.
 
 
If Him I find not, yet I find
The ancient joy of cell and church,
The glimpse, the surety undefined,
The unquenched ardor of the search.
 
 
Happier to chase a flying goal,
Than to sit counting laurelled gains,
To guess the Soul within the soul,
Than to be lord of what remains.
 

PHYSICAL HISTORY OF THE VALLEY OF THE AMAZONS

II

Major Coutinho and myself passed three days in the investigation of the Serra of Erreré. We found it to consist wholly of the sandstone deposits described in my previous article, and to have exactly the same geological constitution. In short, the Serra of Monte Alegre, and of course all those connected with it on the northern side of the river, lie in the prolongation of the lower beds forming the banks of the river, their greater height being due simply to the fact that they have not been worn to the same low level. The opposite range of Santarem, which has the same general outline and character, shares, no doubt, the same geological structure. In one word, all these hills were formerly part of a continuous formation, and owe their present outline and their isolated position to a colossal denudation. The surface of the once unbroken strata, which in their original condition must have formed an immense plain covered by water, has been cut into ravines or carried away over large tracts, to a greater or less depth, leaving only such portions standing as from their hardness could resist the floods which swept over it. The longitudinal trend of these hills is to be ascribed to the direction of the current which caused the denudation, while their level summits are due to the regularity of the stratification. They are not all table-topped, however; among them are many of smaller size, in which the sides have been gradually worn down, producing a gently rounded surface. Of course, under the heavy tropical rains this denudation is still going on, though in a greatly modified form.

I cannot leave this Serra without alluding to the great beauty and extraordinary extent of the view to be obtained from it. Indeed, it was here that for the first time the geography of the country presented itself to my mind as a living reality, in all its completeness. Insignificant as is its actual height, the Serra of Erreré commands a wider prospect than is to be had from many a more imposing mountain; for the surrounding plain, covered with forests, and ploughed by countless rivers, stretches away for hundreds of leagues in every direction, without any object to obstruct the view. Standing on the brow of the Serra, with the numerous lakes intersecting the low lands at its base, you look across the Valley of the Amazons, as far as the eye can reach, and through its midst you follow for miles on either side the broad flood of the great river, carrying its yellow waters to the sea. As I stood there, panoramas from the Swiss mountains came up to my memory, and I fancied myself standing on the Alps, looking across the plain of Switzerland, instead of the bed of the Amazons, the distant line of the Santarem hills on the southern bank of the river, and lower than the northern chain, representing the Jura range. As if to complete the comparison, I found Alpine lichens growing among cactus and palms, and a crust of Arctic cryptogamous growth covered rocks, between which sprang tropical flowers. On the northern flank of this Serra I found the only genuine erratic boulders I have seen in the whole length of the Amazonian Valley, from Pará to the frontier of Peru, though there are many detached masses of rock, as, for instance, at Pedreira, near the junction of the Rio Negro and Rio Branco, which might be mistaken for them, but are due to the decomposition of the rocks in place. The boulders of Erreré are entirely distinct from the rock of the Serra, and consist of masses of compact hornblende.

It would seem that these two ranges skirting a part of the northern and southern banks of the Lower Amazons are not the only remnants of this arenaceous formation in its primitive altitude. On the banks of the Japura, in the Serra of Cupati, Major Coutinho has found the same beds rising to the same height. It thus appears, by positive evidence, that over an extent of a thousand miles these deposits had a very considerable thickness in the present direction of the valley. How far they extended in width has not been ascertained by direct observation, for we have not seen how they sink away to the northward, and towards the south the denudation has been so complete that, except in the very low range of hills in the neighborhood of Santarem, they do not rise above the plain. But the fact that this formation once had a thickness of more than eight hundred feet within the limits where we have had an opportunity of observing it, leaves no doubt that it must have extended to the edge of the basin, filling it to the same height throughout its whole extent. The thickness of the deposits gives a measure for the colossal scale of the denudations by which this immense accumulation was reduced to its present level. Here then is a system of high hills, having the prominence of mountains in the landscape, produced by causes to whose agency inequalities on the earth's surface of this magnitude have never yet been ascribed. We may fairly call them denudation mountains.

At this stage of the inquiry we have to account for two remarkable phenomena. First, the filling of the Amazonian bottom with coarse arenaceous materials and finely laminated clays, immediately followed by sandstones rising to a height of more than eight hundred feet above the sea; the basin meanwhile having no rocky barrier towards the ocean on its eastern side. Second, the wearing away and reduction of these formations to their present level, by a denudation, more extensive than any thus far recorded in the annals of geology, which has given rise to all the most prominent hills and mountain chains along the northern bank of the river. Before seeking an explanation of these facts, let us look at the third and uppermost deposit.

This deposit, essentially the same as the Rio drift, has been minutely described in my former article; but in the north, it presents itself under a somewhat different aspect. As in Rio, it is a clayey deposit, containing more or less sand, and reddish in color, though varying from deep ochre to a brownish tint. It is not so absolutely destitute of stratification here as in its more southern range, though the traces of stratification are rare, and, when they do occur, are faint and indistinct. The materials are also more completely comminuted, and, as I have said above, contain hardly any large masses, though quartz pebbles are sometimes scattered throughout the deposit, and occasionally a thin seam of pebbles, exactly as in the Rio drift, is seen resting between it and the underlying sandstone. In some places this bed of pebbles even intersects the mass of the clay, giving it in such instances an unquestionably stratified character. There can be no question that this more recent formation rests unconformably upon the sandstone beds beneath it; for it fills all the inequalities of their denudated surfaces, whether they be more or less limited furrows, or wide, undulating depressions. It may be seen everywhere along the banks of the river, above the stratified sandstone, sometimes with the river mud accumulated against it; at the season of the enchente, or high water, it is the only formation left exposed above the water level. Its thickness is not great; it varies from twenty or thirty to fifty feet, and may occasionally rise nearly to a hundred feet in height, though this is rarely the case. It is evident that this formation also was once continuous, stretching over the whole basin at one level. Though it is now worn down in many places, and has wholly disappeared in others, its connection may be readily traced; since it is everywhere visible, not only on opposite banks of the Amazons, but also on those of all its tributaries, as far as their shores have been examined. I have said that it rests always above the sandstone beds. This is true, with one exception. Wherever the sandstone deposits retain their original thickness, as in the hills of Monte Alegre and Almeyrim, the red clay is not found on their summits, but occurs only in their ravines and hollows, or resting against their sides. This shows that it is not only posterior to the sandstone, but was accumulated in a shallower basin, and consequently never reached so high a level. The boulders of Erreré do not rest on the stratified sandstone of the Serra, but are sunk in the unstratified mass of the clay. This should be remembered, as it will presently be seen that their position associates them with a later period than that of the mountain itself. The unconformability of the ochraceous clay and the underlying sandstones might lead to the idea that the two formations belong to distinct geological periods, and are not due to the same agency, acting at successive times. One feature, however, shows their close connection. The ochraceous clay exhibits a remarkable identity of configuration with the underlying sandstones. An extensive survey of the two, in their mutual relations, shows clearly that they were both deposited by the same water-system within the same basin, but at different levels. Here and there the clay formation has so pale and grayish a tint, that it may be confounded with the mud deposits of the river. These latter, however, never rise so high as the ochraceous clay, but are everywhere confined within the limits of high and low water. The islands also in the main course of the Amazons consist invariably of river-mud, while those arising from the intersection and cutting off of portions of the land by diverging branches of the main stream always consist of the well-known sandstones, capped by the ochre-colored clay.

It may truly be said that there does not exist on the surface of the earth a formation known to geologists resembling that of the Amazons. Its extent is stupendous; it stretches from the Atlantic shore, through the whole width of Brazil, into Peru, to the very foot of the Andes. Humboldt speaks of it "in the vast plains of the Amazons, in the eastern boundary of Jaen de Bracamoros," and says, "This prodigious extension of red sandstone in the low grounds stretching along the east of the Andes is one of the most striking phenomena I observed during my examination of rocks in the equinoctial regions."¹ When the great natural philosopher wrote these lines, he had no idea how much these deposits extended beyond the field of his observations. Indeed, they are not limited to the main bed of the Amazons; they have been followed along the banks of its tributaries to the south and north as far as these have been ascended. They occur on the margins of the Huallaga and the Ucayall, on those of the Iça, the Jutahy, the Jurua, the Japura, and the Purus. On the banks of the Japura, where Major Coutinho has traced them, they are found as far as the Cataract of Cupati. I have followed them along the Rio Negro to its junction with the Rio Branco; and Humboldt not only describes them from a higher point on this same river, but also from the valley of the Orinoco. Finally, they may be tracked along the banks of the Madeira, the Tapajos, the Xingu, and the Tocantins, as well as on the shores of the Guatuma, the Trombetas, and other northern affluents of the Amazons. The observations of Martius, those of Gardner, and the recent survey above alluded to, made by my assistant, Mr. St. John, of the valley of the Rio Guruguea and that of the Rio Paranahyba, show that the great basin of Piauhy is also identical in its geological structure with the lateral valleys of the Amazons. The same is true of the large island of Marajo, lying at the mouth of the Amazons. And yet I believe that even this does not cover the whole ground, and that some future writer may say of my estimate, as I have said of Humboldt's, that it falls short of the truth; for, if my generalizations are correct, the same formation will be found extending over the whole basin of the Paraguay and the Rio de la Plata, and along their tributaries, to the very heart of the Andes.

Such are the facts. The question now arises, How were these vast deposits formed? The easiest answer, and the one which most readily suggests itself, is that of a submersion of the continent at successive periods to allow the accumulation of these materials, and its subsequent elevation. I reject this explanation for the simple reason that the deposits show no sign whatever of a marine origin. No seashells nor remains of any marine animal have as yet been found throughout their whole extent, over a region several thousand miles in length and from five to seven hundred miles in width. It is contrary to all our knowledge of geological deposits to suppose that an ocean basin of this size, which must have been submerged during an immensely long period in order to accumulate formations of such a thickness, should not contain numerous remains of the animals formerly inhabiting it.² The only fossil remains of any kind truly belonging to it, which I have found in the formation, are the leaves mentioned above, taken from the lower clays on the banks of the Solimoens at Tomantins; and these show a vegetation similar in general character to that which prevails there to-day. Evidently, then, this basin was a fresh-water basin; these deposits are fresh-water deposits. But as the Valley of the Amazons exists to-day, it is widely open to the ocean on the east, with a gentle slope from the Andes to the Atlantic, determining a powerful seaward current. When these vast accumulations took place, the basin must have been closed; otherwise the loose materials would constantly have been carried down to the ocean.

It is my belief that all these deposits belong to the ice period in its earlier or later phases, and to this cosmic winter, which, judging from all the phenomena connected with it, may have lasted for thousands of centuries, we must look for the key to the geological history of the Amazonian Valley. I am aware that this suggestion will appear extravagant. But is it, after all, so improbable that, when Central Europe was covered with ice thousands of feet thick; when the glaciers of Great Britain ploughed into the sea, and when those of the Swiss mountains had ten times their present altitude; when every lake in Northern Italy was filled with ice, and these frozen masses extended even into Northern Africa; when a sheet of ice, reaching nearly to the summit of Mount Washington in the White Mountains (that is, having a thickness of nearly six thousand feet), moved over the continent of North America,—is it so improbable that, in this epoch of universal cold, the Valley of the Amazons also had its glacier poured down into it from the accumulations of snow in the Cordilleras, and swollen laterally by the tributary glaciers descending from the table-lands of Guiana and Brazil? The movement of this immense glacier would be eastward, and determined as well by the vast reservoirs of snow in the Andes as by the direction of the valley itself. It must have ploughed the valley bottom over and over again, grinding all the materials beneath it into a fine powder or reducing them to small pebbles, and it must have accumulated at its lower end a moraine of proportions as gigantic as its own; thus building a colossal sea-wall across the mouth of the valley. I shall be asked at once whether I have found here also the glacial inscriptions,—the furrows, striæ, and polished surfaces so characteristic of the ground over which glaciers have travelled. I answer, not a trace of them; for the simple reason that there is not a natural rock surface to be found throughout the whole Amazonian Valley. The rocks themselves are of so friable a nature, and the decomposition caused by the warm torrential rains and by exposure to the burning sun of the tropics so great and unceasing, that it is hopeless to look for marks which in colder climates and on harder substances are preserved through ages unchanged. With the exception of the rounded surfaces so well known in Switzerland as the roches moutonnées heretofore alluded to, which may be seen in many localities, and the boulders of Erreré, the direct traces of glaciers as seen in other countries are wanting here. I am, indeed, quite willing to admit that, from the nature of the circumstances, I have not here the positive evidence which has guided me in my previous glacial investigations. My conviction in this instance is founded, first, on the materials in the Amazonian Valley, which correspond exactly in their character to materials accumulated in glacier bottoms; secondly, on the resemblance of the upper or third Amazonian formation to the Rio drift,³ of the glacial origin of which there cannot, in my opinion, be any doubt; thirdly, on the fact that this fresh-water basin must have been closed against the sea by some powerful barrier, the removal of which would naturally give an outlet to the waters, and cause the extraordinary denudations, the evidences of which meet us everywhere throughout the valley.