Comparison of the methods of the an-
cients and the moderns with respect to
philosophical discoveries . 1

Definition of the logic of the middle ages ib.

Bacon and Galileo compared . .2

Galileo, his birth and parentage (1564) 3

. was not illegitimate, as generally
supposed . . ib.

• . his father was a man of learning ib.

• exhibits proofs of early talent . 4

•^— constructs models of machinery ib.

studies music and drawing . ib.

sent to the University of Pisa in

1581 ib.

q was disgusted with the Aristote-
lian philosophy . . .5

——- swinging of a lamp, in the ca-
thedral of Pisa, first led him to the
consideration of the vibrations of pen-
dulums . . ib.

Forms of pendulums used by physicians
in the time of Galileo . . ib.

State of mathematical knowledge at that
period .... 6

Galileo appointed professor of mathe-
matics at Pisa, in 1589, when only 25
years of age . . . ib.

adopts the Copernican system of

astronomy . . . 7, 8

Bruno burnt at Rome in the year 1600,
for attacking the philosophy of his time 8

Galileo, his experiments on the fall of
bodies ... 9

appointed professor of mathema-
tics at Padua in 1592 . .10

rapid diffusion of his writings ib.

. his re-invention of the thermo-
meter . . . . ib.

his thermometer described .11

'his thermometer improved by

Leopold de' Medici and others . 11

State of astronomy in the time of Ga-
lileo .... 11-14
Astrological origin of the Saxon names

of the days of the week . 11,12

Diagram, explanatory of . . 12

Delambre's mistaken preference of Kepler

to Galileo . . . .14

Friendly correspondence between Galileo

and Kepler . . . 15

Reflection of Galileo to the professorship

of Padua . . . . ib.

Remarks on the appearance of a new star

in Serpcntarius, in 160I . . 16

Remarks on a new star in Cassiopeia, in
1572 . . . .16

Third appointment of Galileo to the pro-
fessorship at Padua in 1606; and im-
mense number of auditors at his lec-
tures .... ib.

Sector, that instrument invented by Galileo ib.

Gunter's scale, and the proportional com-
pass, remarks on • • 17

Galileo's observations on the loadstone, 17,18

account of his writings that are

now lost . . . 18,19

Telescope, concerning the discovery of, by
Galileo . . .20,26

Porta's claim to the invention of, 20,21

Roger Bacon's claim to the in-
vention of . 22

claim by a Dutchman . 23

S]iectacles, antiquity of . 20

Microscopes constructed by Galileo . 25
Galileo discovers the satellites of Jupiter 26
—— publishes the Nunciut SiJcriui,

or, Intelligences of the Stars . 26

Kepler's astonishment on hearing that
there were more than six planets; and
his demonttration that they could not
exceed that number . . .27

Comparison between theory and experi-
ment . . . . ib.

Fantasticaihypothesos of Huygens, Sizzi,
and others, concerning the probable
number of planets and satellites 28, 29

Galileo's opinion respecting judicial astro-
logy . 29

Disputes to which the discovery of the
satellites gave rise . 31I, 3".

Galileo was the first who conceived that
the longitude might be discovered by
means of the eclipses of Jupiter's satel-
lites . . .32

his observations on the moon 33

.. on Saturn 34, 35

curious anagrams under which

he veiled his discoveries . 34,35

Huygens discovers Saturn's ring in
1656 ... 35

Herschel's subsequent discovery that,
although apparently single, Saturn's
ring is composed of two concentrate
rings, revolving round the planet 35

Galileo observes the crescent appearance
of Venus . . . . ib.

—.— resigns his professorship, and re-
turns to Florence . . 3G