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ON THE FACTS OF EARTHQUAKE PHZ NOMENA. 83 
4th. An account of my own experimental admeasurements, now in pro- 
gress, of the rate of earthquake-wave tfansit through some of the rocky 
and incoherent formations of the earth’s surface. 
5th. An account of the progress made in the construction of a self-regis- 
tering seismometer, with the aid of the British Association. 
NOTE (page 8). 
The obscurity of some passages in the original and the extreme difficulty 
of grasping the meaning of the author almost throughout, with other reasons, 
have made it appear desirable to subjoin a very literal translation of the 
passages of Aristotle quoted in the text. 
The Greek seems unquestionably corrupt in two or three instances. The 
text is from the Oxford Edition of 1837, in 9 vols. 8vo, an amended reprint 
from Becher. 
“The shakings and movements of the earth are next to be spoken of. For the 
cause of this affection of the earth is closely connected with what we have been 
treating of (namely, the wind). 
“Three theories on the subject have been handed down to us by three different 
persons ; namely, Anaxagoras of Klazomene, before him Anaximenes the Milesian, 
and later than these Democritus of Abdera. 
“« Anaxagoras says that the zther by nature rises upward, but that when it falls 
into hollow places in the lower parts of the earth, it moves it (the earth) ; because 
the parts above are cemented or closed up by rain, all parts being by nature equally 
spongy or full of cavities, both those which are above (where we live) and those 
which are below. Of this opinion it may perhaps be unnecessary to say anything, 
as being foolish ; for it is absurd to suppose that things would thus exist above and 
beneath, and that the parts of bodies which have weight would not on every side be 
borne to the earth, and those which are light, and fire rise ; especially since we see 
the surface of the earth to be convex and spherical, the horizon constantly changing 
as we change our place, at least as far as we know. And it is also foolish to assert 
on the one hand that it remains in the air on account of its great size, and on the 
other to say that it is shaken when struck from beneath upwards. And besides 
these objections, it is to be remarked that he has not treated of the attendant cir- 
cumstances of earthquakes, for neither every time or place is subject to these con- 
vuisions. 
ΟΠ “ But Democritus says, that the earth being full of water, and receiving much 
also by means of rain, is moved by this. For when the water increases in bulk, be- 
cause the cavities cannot contain it, in its struggles it causes an earthquake. And 
when the earth becomes partially dried up, the water being drawn from the full 
reservoirs into those which are empty, in passing from one to the other, by its 
movements it causes an earthquake also. 
«« Anaximenes, however, says that the earth when parched up and again moistened, 
_ cracks; and by the masses thus broken off falling on it, is shaken; wherefure 
earthquakes occur in droughts and again in times of rain; in droughts, because, as 
_ we have said, it cracks when highly dried, and then when moistened over again it 
cracks and falls to pieces. Were this the case, however, the earth ought to appear 
_ in many places subsiding. Why then is it that hitherto many places have been 
__very_subject to these convulsions which do not present any such remarkable differ- 
ences from others? Yet such ought tobe the case. And moreover those who think 
_ thus must assert that earthquakes constantly become less and less, and at last cease 
altogether. For the continual condensation of the earth would cause this. Where- 
fore if this be not the fact, it is plain that this is not the correct explanation.” 
» G2 
