light and warmth of his
all-cheering beams. With the advent of night they beheld the Moon, now
increasing, now waning, pursue her irregular path, also to disappear in
the west; whilst, like the bands of an army marshalled in loose array,
the constellations of glittering stars, with stately motion, traversed
their nocturnal arcs, circling the pole of the heavens.

By referring to Book viii., 15-175, we find an account of an interesting
scientific discussion, or conversation, between Adam and Raphael
regarding the merits of the Ptolemaic and Copernican systems, and of the
relative importance and size of the heavenly bodies. By it we are
afforded an opportunity of learning how accurate and precise a knowledge
Milton possessed of both theories, and in what clear and perspicuous
language he expresses his arguments in favour of or against the
doctrines associated with each.

We may, with good reason, regard the views expressed by Adam as
representing Milton's own opinions, which were in conformity with the
Copernican theory; and in the Angel's reply, though of an undecided
character, we are able to perceive how aptly Milton describes the
erroneous conclusions upon which the Ptolemaic theory was based.

In this scientific discussion, it would seem rather strange that Adam,
the first of men, should have been capable of such philosophic
reasoning, propounding, as if by intuition, a theory upon which was
founded a system that had not been discovered until many centuries after
the time that astronomy became a science. By attributing to Adam such a
degree of intelligence and wisdom, the poet has taken a liberty which
enabled him to carry on this discussion in a manner befitting the
importance of the subject.

In the following lines Adam expresses to his Angel-guest, in forcible
and convincing language, his reasons in support of the Copernican
theory:--

When I behold this goodly frame, this World,
Of Heaven and Earth consisting, and compute
Their magnitudes--this Earth, a spot, a grain,
An atom, with the Firmament compared
And all her numbered stars, that seem to roll
Spaces incomprehensible (for such
Their distance argues, and their swift return
Diurnal) merely to officiate light
Round this opacous Earth, this punctual spot,
One day and night, in all her vast survey
Useless besides--reasoning, I oft admire,
How Nature, wise and frugal could commit
Such disproportions, w