Chapter I: The Record of the Rocks

A few days ago, I was walking down the long field back of my house in Hastings-on-Hudson with J. Otis Swift, the naturalist. He stooped and picked up an odd-shaped fragment of quartz. “You could write a volume,” he observed, “about that stone. Long ago, in all probability, it appeared either in granite, a primal stone out of the warm crust of the earth, or as one of the vast mineral group of silicates. The slow seasons weathered it, water took it in solution, and it was deposited afresh as quartz in the cavities of some old basic igneous rock. The action of sea or river rounded it to this large pebble; these scratches may have been made by the glacier that once scratched the top of the Palisades yonder. But these chipped places—here, and here—these were made by the hand of man. The Indians, anywhere from five hundred to fifty thousand years ago, chipped off the flakes and made of it a hammer stone, to shape their stone weapons and implements. You could write a volume about that stone.”

And this monument of the slow fashioning of fire and weather, water, ice, and man, is now a simple field stone, trodden under foot by the careless passerby! I have handled more than five hundred of these worked Indian stones, in the fields within four miles of my house.

We often think of stones as worthless things, unless perhaps as material for building. Yet they are the skeleton that holds the earth together. In the old Greek myth of the flood, Deucalion was told to throw the bones of his mother behind him; and he rightly interpreted this as meaning stones, the bones of Mother Earth. Much of man’s achievement is graven on the stones: from the ancient wordless ruins of Stonehenge to the great pyramids, from the masterpieces of architecture and sculpture to the stone writings of Egypt, Babylon, and the nearest cemetery. The hearthstone commemorates the earliest home, the millstone an early industry. From a rock smitten by Moses’ hand water gushed for the thirsty wanderers; from a stone flung by the sling of David death came to the giant foe of Israel. Commercial products of the stone range from the salt that seasons each meal to the precious metals and the more precious stones called gems. Lastly, the observant men called scientists show us how to read stones like a printed book, in order to understand the early history of the lifeless earth, the beginnings of life upon it, and the forgotten days of the awkward ape-like ancestors of man, and of the earliest man himself.

We do not know how old the earth is, or even how old the earliest rocks are. Estimates by geologists and astronomers, based upon painstaking study, vary between 3,000,000,000 and 25,000,000 years. Carroll Lane Fenton, in “The Building of the Earth” (No. 275) in this series of books, has chosen the conservative figure of 800,000,000 years. In any case, the time occupied by man and his immediate ancestors, the apemen, hardly exceeded one sixteen-hundredth of this, or 500,000 years. A table may make this clearer:

GEOLOGIC TIME TABLE

_Years Ago_ _Era_ _Period_ _Life_

25,000 Recent Man

475,000 Pleistocene Rise of man
(Ice Age)

Cenozoic Pliocene Rise of ape-man
(Recent Life)

40,000,000 Miocene Development of mammals,
Oligocene grass, land forests, etc.
Eocene

140,000,000 Mesozoic Great reptiles
(Middle Life)

360,000,000 Paleozoic Early marine life, fishes,
(Ancient Life) amphibia, swamp forests

600,000,000 Proterozoic No visible trace of life.
(Primordial Life) Primitive forms, jelly fish,
etc.

800,000,000 Azoic (Lifeless) or No life, or one-celled life
Archeozoic (First Life)

Man’s immediate ancestors emerge from the vast geologic history of the earth at the end of the Pliocene and the beginning of the Pleistocene, the Ice or Glacial Age, immediately following. In this, as in all of the tables, the order is stratigraphic, or following the strata of the rocks. Thus the most recent age is at the top, the oldest at the bottom. The Glacial Age, which reached from 475,000 to perhaps 50,000 years ago, was supposed until recently to consist of one great advance and retreat of the ice-fields from various centers. The last forty years has established that there were at least four chief glacial periods, with three interglacial periods, each with its corresponding cold and warm climates. The terraces on either bank of such European rivers as the River Inn, in Austria; the Rhine above Basle, Switzerland, and the Thames, near London, establish a different type of deposit for each glacial period, with different and advancing forms of animal life and human remains. The successive coverings of loam and earth, which washed down from the original sand and gravel terraces left by the glaciers, indicate the same series of glacial and interglacial periods. This loam was retransported in the form of dust by the winds and laid down afresh in layers of varying thickness known as “loess,” a process that still continues in certain districts; this points to the same succession of glacial and interglacial epochs. Finally, the different types of human relics and remains found in the limestone shelters and caverns of Europe point to the same succession of divisions of the Ice Age. The time since the Pliocene may thus be divided as follows:

RECENT GEOLOGIC TIME TABLE

_Years Ago_ _Period_ _Culture_ _Division_ _Life_

9,000-12,000 Neolithic Recent races of men
(Polished
Stone)

25,000 Recent Upper Paleo- Post Glacial Man, or _Homo_
lithic _sapiens_
(Chipped Grenelle race
Stone) Cro-Magnon race
Grimaldi race

Lower Paleo- 4th Glacial _Pre-Homo sapiens_
lithic Neanderthal race

75,000 3rd Inter- Piltdown race
glacial (“dawn” men)

125,000 3rd Glacial

250,000 Pleistocene Eolithic 2nd Inter- Heidelberg race
(Ice or Gla- glacial
cial Age) 2nd Glacial
1st Inter-
glacial
1st Glacial

475,000 Pliocene Eolithic Ape-man (_Pithecan-
thropos_ _erectus_)

There is a common belief that primitive man had to contend with the dinosaurs and pterodactyls of the Great Reptile Age, the Mesozoic. As the first table indicates, this is entirely in error. These reptiles disappeared suddenly from the earth millions of years before the first ape-man appeared. The earliest mammal, a direct transition from the reptile, may have hastened the disappearance of the great saurians by his habit of feeding upon the eggs of the reptiles. Much later came the earliest ape-man; he was contemporaneous with the hairy mammoth, the sabre-tooth tiger, and the rhinoceros—unpleasant enough neighbors. When it came to these monsters, he was less a hunter than the hunted; when he took to the chase, it was after much smaller game.

Science has discovered many facts about the immediate ancestors of man, and the earliest men. Yet all that has been discovered is but a fraction of what is contained in the Record of the Rocks. A few isolated spots on the earth’s surface have been examined; how much of the surface has not even been scratched! Localities in France, England, Germany, parts of Spain, the United States, Java, and elsewhere, have been examined with some care; but there are thousands of miles in these countries where secrets are unrevealed. Whole continents have been hardly touched; South America, Africa, even Asia, perhaps the land in which the races of men originated, are still to be searched. And if all the remains hidden today were uncovered, we would have only a small fraction of the story of the ancient life. Of one race we have found only two teeth, a thigh bone, and the top of a skull; of another, we have only one jaw. Why are there not more fragments? Certain of man’s ancestors were perhaps tree-dwellers; these leave few remains. Their bones are light, brittle, easily destructible; they were crushed in a fall, consumed by beasts, or decayed and disappeared with the dead leaves and wood of the early forests. The apemen and the first men were ground dwellers, hiding among trees and, especially, rocks. It is not such creatures that the Geological Record preserves, as a rule; that record holds chiefly traces of water or marsh creatures, or creatures easily and frequently drowned. When early man, during the harsh Ice Age, took to the caves, he left more traces of his stay. More than this, it has been only seventy years that such prehistoric human fossils have been found; the Gibraltar skull of the Neanderthal race, found in 1848, was practically the first of the long series. Seventy years is not a long period, in which to read the mysteries of five hundred thousand years. We will learn much more in the future.

If the remains of bones are scanty, there is another record of the rocks that yields more: the stone implements of man. Some scientists hold that wooden implements came first, and shell implements second; whether these preceded the use of stones as tools, or came with them, wood and shell have decayed and disappeared. But tools of flint, agate and quartz may not decay in a million years; and men have found every stage of implement widely scattered over the earth. The important thing always is to trace the stages in the development of man—not the exact date when he reached these stages. With different localities, the rate of progress differs enormously. Today, the white races are in the age of the radio and the airplane; backward races still use stone implements; South Sea Islanders and certain African Negroes and bushmen still make use of wood and the sharp-edged shells of land and water molluscs as tools. When Europe was in the age of Shakespeare and Elizabeth, the twin continents of America were largely in the Stone Age. But the order of development, as revealed by the tools, is always similar. There was first a period whose tool remains cannot be identified: because the stones and wooden clubs were used without any shaping changes. Then came the Eolithic Age, or dawn stone age; scientists are still disputing its remains. The tools of this age, called eoliths, have only the rudest working. After this came the Paleolithic, or Old Stone Age—the age of chipped stone. This varies from the crudest flaking to the exquisite laurel-leaf pattern of the Solutrean stage of tool-making (named from the implement station of Solutre, near the Saone River, in France). This Old Stone Age is the period, stretching over more than a hundred thousand years, that we will study here. Next came the Neolithic, or New Stone Age—the age of polished stone. After this came the Bronze Age, and then the Iron Age, blending into the Steel Age. We are still in the last-named period. It is convenient to remember these thus:

THE AGES OF TOOL CULTURE

Iron, and later Steel, Age.
Bronze Age.
Neolithic (New Stone) Age, of polished stones.
Paleolithic (Old Stone) Age, of chipped stones.
Eolithic (Dawn Stone) Age, of stones slightly chipped.

It is now time to answer the questions, who were the immediate ancestors of men, and what can we find out about them.