umanity at large, were doubtless well intended by their
author. He was the first man who brought optical science under the
command of mathematics, by the discovery of the law of refraction of the
ordinary ray through diaphanous bodies; and probably there is scarcely
a name on record, the bearer of which has given a greater impulse to
mathematical and philosophical inquiry than Des Cartes. Although, as a
mathematician, he published but little, yet in every subject which he
has treated he has opened, not only a new field lor investigation, but
also a new road for the investigators to proceed by. His discovery of
the simple application of the notation of indices to algebraical powers,
has totally remodelled the whole science of algebra. His conception of
expressing the fundamental property of curve lines and curve surfaces
by equations between the co-ordinates has led to an almost total
supersedence of the geometry of the ancients. Contemporary with Galileo,
and with a knowledge of the persecution to which that father of physics
was being subjected by the Church, we are tempted to express our
surprise that Des Cartes did not extend the right hand of fellowship,
help, and sympathy to his brother philosopher; but it is, nevertheless,
the fact, that either jealous of the fame of Galileo (as some have
alleged.) or from a fear of being involved in the same persecutions, Des
Cartes abstained from visiting the astronomer, although travelling for
some time near his place of abode in Italy. Lewes, in his "Life of Des
Cartes," says, "Des Cartes was a great thinker; but having said this
we have almost exhausted the praise we can bestow on him as a man. In
disposition he was timid to servility. While promulgating the proofs
of the existence of the Deity, he was in evident alarm lest the Church
should see something objectionable in them. He had also written an
astronomical treatise; but hearing of the fate of Galileo he refrained
from publishing, and always used some chicanery in speaking of
the world's movement. He was not a brave man; he was also not an
affectionate one. There was in him a deficiency of all finer feelings.
But he was even-tempered, and studious of not giving offence."

We are tempted, after a careful perusal of the life and writings of Des
Cartes and his contemporaries, to be of opinion that he was a man who
wished to be considered the chief thinker of his day, and who shunned
and rejected the offers of friendship fro