318 Proceedings of the Royal Physical Society. 
it would be treason at once to the dignity of science and of 
religion, if he sought to help either by swerving ever so 
little from the straight rule of truth." In investigating the 
antiquity of man we are dealing with a question of natural 
history, and are bound by the same methods of research as 
if we were treating of the history of the mammoth or mas- 
todon. Our business as geologists is to examine the rock- 
formations composing the earth's crust, to note their im- 
bedded organisms, and to fix their relative antiquities. 
Wherever the remains of man or of his works occur, there, 
we presume, has been his presence ; and though we cannot 
assign any definite date to the time of such occurrence, we 
are at all events entitled, judging from all the correlative 
circumstances, to say that it took place more than six 
thousand, ten thousand, or twenty thousand years ago. In 
other words, we are bound to deal with Man's antiquity as 
with any other question in geology ; and though our dates 
be merely relative, we can affirm the order of sequence, and 
arrive at some notion of duration from the rate of existing 
operations. 
Abiding by these methods, we find the remains of man 
and of his works gradually receding from the historical into 
the pre-historic ages. In Southern and Western Europe — 
the only regions that have been examined with anything 
like geological accuracy — these remains occur in peat-mosses, 
in lake silts, river-drifts, and cave-earths, and from their 
associated organisms we judge of their relative antiquities. 
If they occur along with the remains of the existing horse, 
ox, sheep, pig, and the like, we know that they are compa- 
ratively recent, and in all probability belong to the historic 
era. If, on the other hand, they are found accompanied by 
remains of extinct species of horses and oxen, we know 
they are of greater antiquity ; and if such horses and oxen 
are not spoken of in history, or represented in human monu- 
ments, then we are entitled to regard them as pre-historic. 
Or again, if they are associated with remains of the great Irish 
deer, the mammoth, mastodon, woolly-haired rhinoceros, 
and other animals long extinct, we feel assured that vast 
changes in physical geography have taken place since their 
