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In the preceding chapter, no mention has been made of the length of the Quaternary sub-division of Cenozoic time, and it will now be our aim to briefly review this period and then investigate the evidence which we have as to how much of this time man has been a portion of its fauna.

With the opening of the Quaternary Period, we come to what is undoubtedly the most remarkable era in all geological time. From a climate which had been, heretofore, uniformly, warmly temperate, with but few exceptions, we come to a period known as the Glacial, in which, by a depression in the temperature, all vegetation and animals in high latitudes were killed; viz.: in the central west—almost to the Ohio River; in Europe—to the northern part of Italy—while the addition of vast quantities of ice to the oceans, destroyed all life in them to about the latitude of the northern portion of the Gulf of Mexico. Nor was this period of cold confined to the northern hemisphere, as the southern part of South America and Africa show. Concerning the cause of the Glacial Period, but little is positively known. Of the theories which have been advanced, it seems very plausible that perhaps two more clearly account for the conditions which must have then existed, if we consider them together, than all the rest.

The geological record teaches us that in the so-called Glacial Period, at least two distinct epochs of low temperature, and the consequential accumulation of ice, are to be definitely discerned. Still further back, we see evidence of glacial action in the Permian Strata, and possibly as far back as the Cambrian formations, although these eras of cold are not comparable with the period at the beginning of the Quaternary time. Croll, the Scottish physicist, first called attention to the fact that at certain regular intervals of time, the precession of the equinoxes, and the eccentricity of the earth’s orbit, would so act in conjunction as to render favorable a great many conditions which would certainly all point toward a period of extreme cold. He calculated that the earth was traveling around the sun in an ellipse of maximum eccentricity, and that winter was occurring in the northern hemisphere when the earth was furthest from the sun, for the last time some quarter of a million years ago. About eighty thousand years after this date, the coincidence of the two phenomena reached a maximum effect, and about eighty thousand years later, climatic conditions were again about as we have them to-day. Upon this hypothesis, another period of extreme cold must have existed some one-half million years earlier, as calculations upon the same premises as were used in the last computation will show. It is likewise true that, according to this theory, there must have been at least one other such period further back in geological time, and it is now to be seen whether our records, as shown by the strata, establish these facts.

Prior to the enunciation of this theory by Croll, the famous English geologist, Sir Charles Lyell, from measurements of the strata, had calculated that the last period of glaciation occurred about as Croll stated, and that a period of cold and ice far more intense and extensive occurred some four or five hundred thousand years earlier. Mr. Laing has shown that, in order to make such conditions as must have existed at this time, not only is a low temperature necessary, but a certain amount of land must have an elevation sufficient to give the required initial fall to the ice river, so that it may move over the obstacles in its way, and that the higher such elevations in the Arctic zones, and the greater the humidity of the air when it strikes such elevated polar plateaux, the more augmented will be the probability of glacial activity. The rapidity of the glacier’s movement can have no bearing upon the duration of the glacial period, inasmuch as a certain length of time may have been required for the ice-cap to form and push forward to a certain place, and it may have remained there for an indeterminate period, governed only by the amount of snow deposited upon the original source, and the rapidity of melting at the moraine. In Eastern England, no less than four distinct boulder clays have been found separated by the débris deposited from the moraines of each ice sheet, and a few hundred miles away in France, the record is so certain that we know that the Arctic fauna and flora gave away twice for that of the warmer parts of the Temperate zones.

We are certain that both that portion of Scandinavia and Canada, which were the centers of the great European and American ice-caps, had an elevation greatly in excess of what it is to-day, at the time of the glacial epoch. During the first glaciation, Eastern Canada, or that part south of Hudson’s Bay, was certainly twenty-five hundred feet higher than it is now, and the area covered by ocean formations or marine beds to the southward, show that at the same time these sections were very much lower than they are at the present day. On the other side of the Atlantic Ocean, the elevation in Norway was at least a couple of thousand feet more than at present; while both England and Ireland have risen a considerable amount since this period.

There are other ways by which we may form some estimate of the time which has elapsed since the melting away of the great glaciers, besides that given by Croll. From measurements taken on Table Rock, at Niagara Falls, which we know has receded in post-glacial times from Lewiston to the place which it occupies at present, we are certain that Lyell was not far wrong when he estimated this to have taken at least sixty thousand years. Shaler, on entirely different grounds,—mainly the redistribution of certain angiosperms—has arrived at figures in excess of these. Calculations made upon the canyons of the Columbia, San Joaquin, and Colorado Rivers, all show the estimations previously given to be conservative. Of course, the figures given will apply only to the time which has elapsed since the melting of the American ice-cap, as we have no means of knowing that the American and European glaciers acted at all in unison in their retreat to the northward. The manner in which we can get some idea of the length of time required to account for the enormous quantity of work done in the Champlain period, is by taking into account the deposits which lie in almost all of the great river valleys which were covered by the glaciers, or whose watersheds were made into lakes by the subsidence of the land to the north, and the rapid melting of that portion of the ice-cap which contained stones, dirt, and other material picked up in the travels of the glacier across the country. The Rhine, the Rhone, and the Danube in Europe, and the St. Lawrence, the Connecticut, and the Mississippi in America, all flow through valleys lined with cliffs of loess. These accumulations overlying the coarser sands and gravels, and conforming to the river valleys, have been measured in the case of the Rhine, and were found to be about eight hundred feet in depth. It is unreasonable to suppose that these deposits being, as they are, material thrown down out of the water after the rivers had lost their transporting power, could have accumulated at a greater rate than that now going on in the rivers, such as the Mississippi and the Nile, to-day, and if this was the case, these deposits must have taken no less than three hundred and twenty-five thousand years to form. Inasmuch as this work was all done during the Champlain period, this figure can be safely taken as the minimum for the measure of the duration of that time.

Arriving now at the recent period of Quaternary time, we find in Europe evidences of a very short and less intense period of cold; in the remains of the reindeer and other Arctic animals in southern France. Associated with these, although of a later period, we find the bones of the cave bear, hyena, and lion, and in many of the localities intimately associated with these are the bones of man. In fact, since the first discovery of the paleolithic implements in the gravels of the Somme, there have been almost countless finds of human remains in England, France, Belgium, Spain, Italy, and Greece, in Europe; Algiers, Morocco, Egypt, and Natal, in Africa; in China, Japan, India, Syria, and Palestine, in Asia; in Brazil and Argentina in South America, and in no less than ten States of this country, associated with stone implements or paleoliths, and all of which, dating from the beginning of the Quaternary period, have established the certainty of human existence during the entire Quaternary era, beyond the possibility of doubt.

The evidences of the existence of the human species during Tertiary time are many, and hardly a year goes by without adding another discovery of human remains in the deposits belonging to this period. To begin with, the existence of man so generally and widely distributed as we find him to be at the beginning of the Quaternary period, is almost prima facie evidence of his occupation of the earth for some time previous. With the means of communication and the motives for it, such as they must have been at this remote period, we know that thousands of years would have been required to scatter any species all over the earth, as we have seen that man was from the locations of the remains found. Further than this, there are three well-authenticated cases where the bones of Tertiary animals have been found, upon which there were cuts made by edged tools, which could have been made only by human agency. Since these have been discovered, crude implements as well as human bones have been found in no less than a dozen places in both the Eastern and Western Hemispheres, which attest, beyond doubt, to man’s having existed since the Middle Miocene or early Pliocene time. We not only have the opinions of such authorities as Rames, Hamy, Mortillet, Quatrefages, and Delauney, to accept in this matter, but the more recent thorough investigations of Laing and Haeckel.

Turning now from geological evidence to that founded upon other observations, as to the length of time man has been an inhabitant of the earth, perhaps one of the most interesting discoveries was that of the Tumuli or mounds of shells of such animals as the oyster, cockle, limpet, etc., and, along with this, the bones of birds, wild animals, and fish, together with stone implements and rude pottery. These kitchen-middens were first discovered in Denmark, but they have since been found in many countries where savages have lived along the coast. In many of the Swiss lakes, such as Zurich and Neufchatel, there have been found piles driven into the ground, around which, in dredging, human bones, as well as stone implements, have been brought up, and which are now known to have been the dwelling-places and remains of prehistoric peoples, who located in this manner so as to protect themselves from prowling wild animals and from their savage neighbors. From the amount and character of these deposits, we are forced to assume that the habitations were used for a long period, and from geological computation of the time required to deposit the silt around these piles in the Swiss Lake-villages, and from the similarity of the remains in the Danish peat-mosses and the kitchen-middens no period could be assigned to their antiquity of less than seven thousand years.

Our earliest record of historic man is found in the Valley of the Nile, where we can say with certainty that, over seven thousand years ago, there existed a high state of civilization under the old Egyptian Empire. Menes was the first recorded king who sat on the throne, and during the six dynasties of kings which composed this period, we see the rise to supremacy of Memphis, the building of the pyramids, the accumulation of a varied and extensive literature, and the perfection of the industrial and fine arts. In fact, so faithfully and indestructibly were the lines of human faces reproduced upon stone and other materials, that, at this day, we have no difficulty in identifying the different races of men from their resemblance at the present time. Menes, himself, carried to completion the great engineering feat of turning the course of the Nile so as to obtain a site for his capital, at Memphis. His successor was not only a patron but a practitioner of the art of medicine. From the monuments and papyri of the great tombs of Ghizeh and Sakkara, we have learned so much of the social and political life of Egypt at this period through the deciphering of the Rosetta stone by Champollion, that we may be said to have a very accurate knowledge of mankind, as his existence was conditioned in Egypt from four to five thousand years before the beginning of our present era. From Memphis, the seat of the government first shifts to Heracleopolis, and then to Thebes, and, during these changes, we see Egypt go back into the night of semi-barbarism (comparatively speaking), and after a long period of time to again develop a high state of civilization, under a new language and a new religion, in the eleventh dynasty. Egyptian influence extended from the equator on the south, to southern Syria on the north, and Isis and Osiris were the deities that commanded the veneration of the then civilized world. The kings of this dynasty built the famous labyrinth of Fayoum, where in the desert was formed a large artificial lake with tunnels and sluices so arranged that the annual inundations of the Nile were partially controlled by allowing the surplus water to fill this lake, and in the time of a drouth, letting it out to irrigate the valley as needed. Many temples, obelisks, and statues were erected, and the period was one of social and literary activity. About two thousand years before Christ, the seat of the government was transferred from Thebes to the Delta, and, shortly after this, the Hyksos dynasty began with a conquest by these invaders, who laid all Egypt under tribute. The conquerors adopted both the civilization and the religion of their subjects, and reigned over Egypt somewhat more than five hundred years. Their expulsion marks the beginning of the new empire, which extended the Egyptian influence from the Persian Gulf to the Mediterranean, and subjugated both Babylon and Nineveh. From this time on, we are on certain and firm historical grounds, and with the founding of the great library at Alexandria, by Ptolemy Philadelphus, Egypt received her last great literary impulse, and since the fourth century of this era the part which she has played in the struggle of humanity has been inconsiderable. From other data gathered by Horner, who sunk numerous shafts across the Nile Valley at Memphis, and who brought up copper knives and pottery from depths approximately of sixty feet, it has been calculated, from the rate of deposition in that valley to-day, that these remains are upward of twenty-five thousand years old. In other places, Paleoliths have been found that are undoubtedly very much older than the oldest temples and tombs. Furthermore, we know that in all the traditions of this country, the first inhabitants are represented as being autochthonous, which, if correct, must mean a very great state of antiquity, so far as man is concerned; if it be granted that this Egyptian civilization, which is known to have existed at Memphis, had to develop of its own accord in the Valley of the Nile, abundantly fertile though it always has been.

In the valleys of the Euphrates and Tigris Rivers, we have further evidence of the existence of a high state of civilization, as taken from the cylinder of Sargon I, which reads, “Sharrukin the mighty king am I, who knew not his father, but whose mother was a royal princess, who, to conceal my birth, placed me in a basket of rushes closed with pitch, and cast me into the river, from which I was saved by Akki, the water-carrier, who brought me up as his own child.” The date of this king is generally accepted as about four thousand years before Christ, and his exploits have been found pictured and described on the relics taken from Cyprus, Syria, and Babylonia. He did for Mesopotamia what Menes did for Egypt, and the prestige of his arms, and the renown of his civilization, spread over all Asia Minor. As a patron of literature, he founded some of the most famous libraries in Babylonia, and compiled a work of seventy-two volumes on Astronomy and Astrology, which was even translated into Greek. From recent researches, which have resulted in the finding of a great many clay tablets from the libraries of Mesopotamia, it seems certain that this Sargon I, upon his ascension to the throne, found the Accadian people (he was a Semite) already enjoying a high civilization, with sacred temples, a sacred and profane literature, and one who had a large and well-ordered knowledge of astronomy, as well as of agriculture and the industrial arts. From the archæological remains which have been discovered, and, in particular, the marble statue of a king by the name of David, which was recently found at Bisinya, and whose antiquity is probably greater than 4,500 B. C., it is entirely conservative to assume that Chaldean civilization was as old, if not older, than that of Egypt; while no figure can be set upon the length of time which was required in these fertile valleys for this state of affairs to develop from a condition of barbarism.

In China, strangely enough, where the oldest historical records would be expected, we can find nothing to compare with the Egyptian papyri or the Chaldean clay-cylinders, and competent authorities are well agreed that there is great reason to suppose that much of the early civilization was brought from Accadia. In any case, at the dawn of history, we find China just as she is to-day:—an overpopulated, agricultural country, where blind imitation of predecessors ruled, and, consequently, progress, unless brought in by conquest, is extremely slow. If the empire was founded, as has been supposed, by an Accadian invasion or immigration, which must have occurred about 5,000 B. C., or at least before the time of Sargon I, then these wanderers drove out the aboriginal inhabitants, the Mioutse, who have been crowded at last into the mountains of the western provinces. Certain it is that no greater date can be assigned to the civilization of this country, at the beginning of its historical record, than about 2,750 B. C., which time is known in Chinese tradition as the “Age of the Five Rulers.”

Perhaps next in order of antiquity, comes the small country known as Elam, lying between the Tigris River and the Lagros Mountains, and extending to the south along the eastern shore of the Persian Gulf to the Arabian Sea. As in both Egypt and Chaldea, this country was brought into prominence by an aggressive and warlike king,—the famous Cyrus of history,—and, fortunately, his clay-cylinder; from one of the magnificent libraries of Susa, or Shushan; was recently found by Mr. Rassam, amid the débris composing the mound, which is now the only mark left to show where these great centers of population once were, in the fertile valleys and coast plains of this part of Asia; and this cylinder is now kept, with hundreds from like sources, in the British Museum at London. On this memorial cylinder, Cyrus gives his genealogy and an account of his exploits, and we find that he came from a line of kings, and held to the popular faith of his country, thanking and petitioning the whole Elamite Hierarchy of gods. Cyrus carried the Elamite arms into southern Syria and Palestine, and overthrew Mesopotamia about 2,300 B. C. It was the reaction from this conquest that caused some of the most gigantic struggles of antiquity.

Of the Phœnician cities of Tyre and Sidon, no definite historical record can be found earlier than from fifteen hundred to two thousand years before Christ. The Hittite civilization and influence we find at their height at about the same time, but here we can get no inkling of a greater antiquity for man than that given in the Middle Egyptian Empire. In the cities of Troy and Mycenæ, we find civilization at its crest some five hundred years later, and it is not until we come to Arabia that we again find evidence of such high antiquity as we find in Chaldea and Egypt. The old kingdom of Saba was built upon the ruins of a still older, known as Ma’in, and the former was in its decline as an empire at the beginning of the eighth century, B. C. Now, contemporary history shows that this country has gone through all the transformations which Egypt and Chaldea had, and if this is also true of the Ma’in kingdom, then a date of great antiquity must be given to it. But these are not certainties, while in the cases of Chaldea and Egypt there can be no mistake. The Israelite civilization was at its height under David and Solomon, about contemporaneously with that of Troy and Mycenæ, and even the Hebrew tradition does not attempt to antedate the year 2,000 B. C., so that we can obtain no information from this source. Greece flourished but five hundred years before the present era, and even if we regard Homer as authentic, no more remote date can be given to their earliest civilization than that of the attack by the Hellenes upon Troy, which was about 1,000 B. C.

In the Western Hemisphere archeologists are every year making valuable discoveries in Mexico and Peru which will probably give a remote date for the civilizations which flourished in these countries long before the conquests of the Spaniards. The great pyramids of the Sun and Moon on the Mexican plateau and the similarity of their design and orientation with the Egyptian all point to an interchange of ideas between the East and the West in prehistoric time.

The geological table given at the close of this chapter may be of interest, as a careful consideration of it, and the foregoing facts, will show the real value of man in nature. That man is ascendent now, does not, in the light of experience, mean necessarily that he will by any means remain so. In the warm Champlain period, we know that brute mammals thrived and attained gigantic size, and, as Dana aptly remarks, “the great abundance of their remains and their conditions show that the climate and food were all that could have been desired.” Yet the mastodon and the cave-bear have gone, together with countless other species which have become extinct, and, if science teaches anything at all, it tells us that nature delights in fostering one species at the expense of another. In the case of man, we most clearly see this. “For the historical succession of vertebrate fossils corresponds completely with the morphological scale which is revealed to us by comparative anatomy and ontology. After the Silurian fishes come the dipnoi of the Devonian period,—the Carboniferous amphibia, the Permian reptilia and the Mesozoic Mammals. Of these again, the lowest forms, the monotremes, appear first in the Triassic period; the marsupials in the Jurassic, and then the oldest placentals in the Cretaceous. Of the placentals, in turn, the first to appear in the oldest Tertiary period are the lowest primates, the prosimiæ, which are followed by the simiæ, in the Miocene. Of the carrhinæ, the cynopitheci precede the anthropomorpha; from one branch of the latter, during the Pliocene period, arises the apeman, without speech, and from him descends finally the speaking man.

“Since the germ of the human embryo passes through the same chordula-stages as the germ of all other vertebrates; since it evolves, similarly, out of the two germinal layers of a gastrula, we infer by virtue of the biogenetic law, the early existence of corresponding ancestral forms. Most important of all is the fact that the human embryo, like that of all other animals, arises, originally, from a single cell, for this stem-cell—the impregnated egg cell—points, indubitably, to a corresponding unicellular ancestor, a primitive Laurentian protozoon.”

In the foregoing quotation, Haeckel clearly states what every geologist and embryologist plainly knows to be the truth, and in this case, as in all others, does it hold good: