What I have written in this and the preceding chapters, on the differences and likenesses between apes and man and the probable steps of the transition from ape to man, may assist the reader to form a judgment as to the importance of such remains of extinct races of men as the skeleton of the Sainte Chapelle, the Heidelberg jaw, and the Piltdown jaw and cranium lately dug up in Sussex, in helping us to further knowledge of those steps. It should be definitely noted that we have not yet found any extinct animals, definitely to be classed as apes, which come nearer to man than the chimpanzee and gorilla, although we are led to infer that such creatures existed, and that their fossil remains will probably some day be discovered. On the other hand, we have in the jaw and skull recently discovered in the gravel of Piltdown, in Sussex, evidence of a man-like creature which was in most important features more ape-like than any fossil man yet discovered.

CHAPTER XXX
THE MISSING LINK

UNTIL the discovery of the wonderful fossil jaw in the gravel of Piltdown, near Lewes in Sussex, a favourite view as to the probable relationship of man and existing apes was, that if you could trace back the pedigree of man and of the chimpanzee into remote antiquity far back in the Tertiary period—probably in the early Miocene—you would arrive at a smallish creature with, proportionately to its size, larger jaws and teeth than any modern man, yet smaller than those of the living man-like apes, and with a brain not two-thirds the size of that of the least developed of modern savages, yet larger (in proportion to its general bulk) than that of the gorilla, chimpanzee, orang, and gibbons. This hypothetical creature would represent, it was held, the common ancestor of the two great "strains" or "stocks" one of which in the course of gradual modification gave rise to our living "humanity," and various non-surviving offshoots on the way; whilst the other gave rise to the company of great apes, with their tremendous jaws and dog-teeth, their small brains, and great bony skull-crests for the attachment of huge jaw muscles.

It was insisted that the obvious and immediate suggestion when once man's descent from animal ancestry was admitted, namely, that man has taken his rise from the most man-like animals we know—the great apes—is erroneous. The public was warned that they must not jump to such a conclusion; it was too obvious, too facile. The "celebrated ape of the Darwin shape," which popular songs made familiar to a wide public, was declared to be only a remote rustic, not to say brutalized, cousin of humanity, not in the direct line happily! Our real ancestors, it was declared, were mild, intelligent little creatures, animals, it is true, but animals which hastened to separate their mixed qualities in two divergent lines of descent—(1) the intelligent, mild-mannered clan who ceased to climb trees, and walked uprightly on the soles of their feet, whilst their teeth grew smaller and smaller, and their brains grew bigger and bigger; and (2) the violent tree-climbing members of the family, who refused to stand up, and acquired bigger and bigger jaws and teeth, whilst their brains remained small, their temper morose, and their conduct violent.

Fig. 23.—Comparison of the right half of the lower jaw of A, Modern European; B, Eoanthropus from Piltdown; and C, Chimpanzee. The size of the drawings is two-thirds of the linear dimensions of the actual specimens. The dotted outline in B represents the part which was wanting in the original specimen and was thus re-constructed by Dr. Smith Woodward. X in A is the bony chin or "mental protuberance"; in B and C it marks that part of the jaw which would become the mental protuberance were the palisade or line of teeth retracted as in A.

Old writers before the days of Darwin had talked and written about the "missing link," though I cannot say who first used the term in reference to a creature intermediate between man and apes. Sir Charles Lyell in 1851 made use of the term in regard to extinct animals which were intermediate in structure between two existing types. A learned and able writer—the Scotch judge, Lord Monboddo—in the later half of the eighteenth century put forward a theory of the development of mankind from apes such as the orang, quite independently of any general theory of "transformism" or of the progressive development of the animal and vegetable worlds, from simple beginnings. Lord Monboddo, in the absence of any knowledge of a "missing link," or of animals intermediate between man and the highest living apes, made reasonable speculations (based on wide study of anthropology and ancient philosophy) as to the passage from the monkey to man. He regarded man as of the same "species" as the orang-utan. He traced the gradual elevation of man to the social state as a natural process determined by "the necessities of human life." He looked on language (which he said is not "natural" to man in the sense of being necessary to his self-preservation) as a consequence of his social state. His views about the origin of society and language, and the faculties by which man is distinguished from the brutes, are in some interesting ways similar to those of Darwin. He conceived man as gradually elevating himself from an animal condition in which his mind is immersed in matter to a state in which mind acts independent of body. He was ridiculed and declared to be half mad by his co-temporaries (among them Samuel Johnson), although he was, philosophically, far in advance of those with whom he came into contact. Darwin's views on the "Descent of Man" were met in the same contemptuous spirit at first. But he held a much stronger position than Monboddo, having first of all established the general theory of organic evolution, and having, further, a well-established mass of evidence at his command in regard to the relationship of man and apes. Further, he had that wonderful champion, Huxley, to fight for him. Huxley's book, "Man's Place in Nature," originally given as lectures which I, then a boy, attended, placed the evidence of the close relationship of man and the higher apes in the clearest way before the public, and, indeed, established the identity of the structure of man with that of the ape, bone for bone, muscle for muscle, and nerve for nerve.

Still, there was always a gap—a place unfilled—between the large-brained, small-jawed man and the small-brained, large-jawed ape. The link was missing. It was hoped, when in 1859 the human workmanship of the flint axes found with the bones of extinct animals in our river gravels was recognized, that the bones of the men who made the flint axes would turn up alongside of them, and that they would show characters intermediate between those of modern man and the great apes. But no such human bones ever were found in the older gravels deposited as terraces along their beds by the rivers of Western Europe. Human bones, and more or less complete human skulls, of a highly-developed modern type (the Cromagnards) were found in caves associated with flint tools of a different character to those common in river gravels. Then we heard a good deal about the strangely flat skull-top, or calvaria, found in a cave near Dusseldorf on the Rhine, associated with the preaching of a certain hermit named "Neuman" (= Neander). The valley was called "the Neanderthal," and the skull-top thus came to be called the "Neanderthal skull." Some authorities regarded the Neanderthal skull as that of an outcast idiot! Huxley studied it minutely, and compared it to that of Southern Australian black-fellows, and held that it took us no nearer to the apes than they did. Then an unsatisfactory small flat skull-top, together with a long, straight thigh-bone, was found in a gravel in Java, and the name "Pithecanthropus" was applied to these remains. Still we had got no nearer to any knowledge of the missing link.