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218 - REVIEWS. 
ever the negative evidence may be worth, it applies to Pliocene as 
well as to Miocene times. 
Moreover if the Engis skull really belongs to the period of the 
extinct mammalia, and yet agrees with many a European skull of 
the present day, then, as Professor Huxley well observes, “the 
“ first traces of the primordial stock whence man has proceeded need 
“ no longer be sought by those who entertain any form of the doc- 
“ trine of progressive development in the newest tertiaries, but that 
“ they may be looked for in an epoch more distant from the age of 
“ the Elephas primigenius than that is from us.” 
If, during the immense period which has elapsed since the Engis 
man lived in company with the Mammoth, the Cave Bear, the Cave 
Hyaena, the woolly-haired Bhinoceros, and other extinct mammalia, 
so slight a change has occurred in the form of the human cranium, how 
long must it have taken to bridge over the great gulf between the 
genus Homo and his nearest relatives among the Apes. Misled by 
early education, trusting too much to the negative evidence afforded 
by the absence of human remains in tertiary strata, Geologists have 
hitherto adopted the hypothesis of separate creations; and the 
appearance of new species is perhaps the only case remaining in 
which men of science are still satisfied to accept miraculous interfer¬ 
ence as a satisfactory explanation of a scientific fact. In some respects 
the position of the question resembles the phenomenon presented 
to Astronomers by the perturbations of Uranus. They might have 
accounted for these perturbations by the hypothesis of miracles; they 
might have argued that no trace of an exterior planet had ever been 
discovered. But they knew better the value of negative evidence in 
science ; they trusted more fully in the universality of law, and their 
faith was rewarded by the discovery of Neptune. 
Or, again, let us take the problem presented to us by the Sun. It 
is difficult to understand how light and heat can have been emitted 
for so long a period as that demanded by Geologists. Lately, in¬ 
deed, a theory has been suggested in explanation by Hr. Mayer of 
Heilbronn and by Mr. W aterston ; it is supported by several eminent 
physicists, as, for instance, Professor Tyndall and Professor W. 
Thomson, but it cannot be said to be generally adopted. Still, no 
astronomer, so far as we are aware, has ever proposed in a scientific 
treatise to account for the phenomenon by miraculous inter¬ 
ference ; and it is remarkable that a hypothesis for which there is 
not a vestige of evidence, which is indeed opposed to the whole 
tenor of scientific research, and which has been universally rejected 
in every other case, should have been almost as universally adopted 
in explanation of the successive Origin of Species. 
Without, then, expressing any decided opinion as to the age of 
Man, estimated in years, we feel compelled to demand for him a 
greater geological antiquity than Sir Charles Lyell is prepared to 
admit. It is immaterial, in this respect, whether we adopt the theory 
of Natural Selection which we owe to the genius of Darwin; any other 
