uture success in life.

[3] De Insidentibus in Fluido.

[4] Opere di Galileo. Milano, 1810, vol. iv. p. 248-257.

Through the Cardinal del Monte, the brother-in-law of Ubaldi, the
reigning Duke of Tuscany, Ferdinand de Medici was made acquainted with
the merits of our young philosopher; and, in 1589, he was appointed
lecturer on mathematics at Pisa. As the salary, however, attached to
this office was only sixty crowns, he was compelled to enlarge this
inadequate income by the additional occupation of private teaching, and
thus to encroach upon the leisure which he was anxious to devote to
science.

With this moderate competency, Galileo commenced his philosophical
career. At the early age of eighteen, when he had entered the
university, his innate antipathy to the Aristotelian philosophy began to
display itself. This feeling was strengthened by his earliest inquiries;
and upon his establishment at Pisa he seems to have regarded the
doctrines of Aristotle as the intellectual prey which, in his chace of
glory, he was destined to pursue. Nizzoli, who flourished near the
beginning of the sixteenth century, and Giordano Bruno, who was burned
at Rome in 1600, led the way in this daring pursuit; but it was reserved
for Galileo to track the Thracian boar through its native thickets, and,
at the risk of his own life, to strangle it in its den.

With the resolution of submitting every opinion to the test of
experiment, Galileo's first inquiries at Pisa were directed to the
mechanical doctrines of Aristotle. Their incorrectness and absurdity
soon became apparent; and with a zeal, perhaps, bordering on
indiscretion, he denounced them to his pupils with an ardour of manner
and of expression proportioned to his own conviction of the truth. The
detection of long-established errors is apt to inspire the young
philosopher with an exultation which reason condemns. The feeling of
triumph is apt to clothe itself in the language of asperity; and the
abettor of erroneous opinions is treated as a species of enemy to
science. Like the soldier who fleshes his first spear in battle, the
philosopher is apt to leave the stain of cruelty on his early
achievements. It is only from age and experience, indeed, that we can
expect the discretion of valour, whether it is called forth in
controversy or in battle. Galileo seems to have waged this stern warfare
against the followers of Aristotle; and such was the exasperation which
was excit