PRIMITIVE ASTRONOMY. 
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others, that “ the extreme part of the heavenly sphere is earthy 
and solid ;” and others, again, imagined that the blue sky con- 
sisted of “ air condensed by fire so as to assume the substance 
of ice.-’-’ This firmament was supposed to revolve around the 
Earth, and the stars were believed to be attached to it, their 
nature again being the subject of much consideration and 
discussion. According to some of the Greek astronomers they 
were “ circular bodies of condensed air containing fire,” whilst 
others regarded them as “ compressed fire fed by exhalations 
from the Earth,” and others, again, as “ stones ignited by the 
fiery firmament.” 
The last theory was propounded by Anaxagoras, a Greek 
philosopher, who probably entertained this idea from the exa- 
mination of aerolites, of which one of large dimensions fell 
during his lifetime (about the year 468 B.c.), in Thrace. 
His views concerning the heavenly bodies generally were 
rather more rational than those previously adopted, and in 
some cases he arrived at conclusions which have been confirmed 
by the revelations of modern science. 
Whilst, for example, one observer compared the Sun to a 
wheel, of which the spokes were the rays, and another likened 
it to a “ bowl or hollow hemisphere” (a solar eclipse taking 
place when the luminous convexity is turned upwards and the 
dark concavity towards the Earth), this bowl being no larger 
than the Sun really appears to the naked eye, namely, about the 
width of a man's foot; — whilst, we say, these were the extra- 
ordinary notions entertained by some philosophers concerning 
the orb of day, Anaxagoras had arrived at the conclusion that 
the sun is a mass of ignited stone, and his ideas of its size were 
also somewhat advanced, for he believed it to be “ larger than 
the Peloponnese.” But what is more remarkable, he believed 
the Moon to be an “ Earth having its plains, mountains, and 
valleys, and likewise its inhabitants.” He considered that it 
derived its fight from the Sun ; arrived at correct conclusions 
as to the cause of eclipses of the Moon, believing them to be 
due to the interposition of the earth between the Sun and Moon, 
and on all subjects he wrote with “ boldness and freedom.”* 
The reader will not be much surprised to hear that as a 
result of this enlightenment he was persecuted by the adherents 
of the established religion; compelled to move from city to 
city ; was accused of impiety, imprisoned, fined, and that he 
at length emigrated. He died at the age of seventy, about 
430 b.c. 
Anaxagoras not only wrote on astronomy, but also on the 
* These quotations concerning the astronomical theories of the ancients 
are from Sir G. C. Lewis’s work. 
