ing the proofs.

ROBERT S. BALL.

_Observatory_, CO. DUBLIN,
_April_ 26, 1889.

TIME AND TIDE.

LECTURE I.

It is my privilege to address you this afternoon on a subject in which
science and poetry are blended in a happy conjunction. If there be a
peculiar fascination about the earlier chapters of any branch of
history, how great must be the interest which attaches to that most
primeval of all terrestrial histories which relates to the actual
beginnings of this globe on which we stand.

In our efforts to grope into the dim recesses of this awful past, we
want the aid of some steadfast light which shall illumine the dark
places without the treachery of the will-o'-the-wisp. In the absence
of that steadfast light, vague conjectures as to the beginning of
things could never be entitled to any more respect than was due to
mere matters of speculation.

Of late, however, the required light has been to some considerable
extent forthcoming, and the attempt has been made, with no little
success, to elucidate a most interesting and wonderful chapter of an
exceedingly remote history. To chronicle this history is the object of
the present lectures before this Institution.

First, let us be fully aware of the extraordinary remoteness of that
period of which our history treats. To attempt to define that period
chronologically would be utterly futile. When we have stated that it
is more ancient than almost any other period which we can discuss, we
have expressed all that we are really entitled to say. Yet this
conveys not a little. It directs us to look back through all the ages
of modern human history, through the great days of ancient Greece and
Rome, back through the times when Egypt and Assyria were names of
renown, through the days when Nineveh and Babylon were mighty and
populous cities in the zenith of their glory. Back earlier still to
those more ancient nations of which we know hardly anything, and
still earlier to the prehistoric man, of whom we know less; back,
finally, to the days when man first trod on this planet, untold ages
ago. Here is indeed a portentous retrospect from most points of view,
but it is only the commencement of that which our subject suggests.

For man is but the final product of the long anterior ages during
which the development of life seems to have undergone an exceedingly
gradual elevation. Our retrospect now takes its