C 579 3 
51. Another example of the fame kind happened 
at' * Manila, one of the Philippine iflands, in the 
year 1750. This alfo was attended with violent 
earthquakes, to which that ifland, as well as the reft 
of the Philippines, is very much fubjedh 
32. We may add to thefe, the many inftances of 
V&ft quantities of -f* pumice ftones, which have been 
fometimes found floating upon the fea, at fo great a 
diftance from the fhore, as well as from any known. 
Volcano, that there can be little doubt of their being 
thrown up by fires fubfifting under the bottom of the 
Ocean. 
33. From thefe inftances, we may, with great 
probability, conclude, that the fires of volcanos pro- 
duce earthquakes : I do not, however, fuppofe, that 
the earthquakes, which are frequently felt in the 
neighbourhood of volcanos, are owing to the fires 
of thofe volcanos themfelves ; for volcanos, giving 
paflage to the vapours that are there formed, lhould 
rather prevent them, as in the inftance at St. Chri- 
ftopher’s, before-mentioned. 
34. We alfo meet with frequent inftances con- 
firming the fame thing amongft the Andes. Antonio 
d’Ulloa (fpeaking of what happens amongft thefe 
mountains) fays, tc Experience thews us, that, upon 
<c the frefti breaking out of any volcano, it occafions 
ct fo violent a fhock to the earth, that all the villages, 
c< which are near it, are overthrown and deftroyed, 
* See Philof. Tranf vol. Jclix. p. 459. 
t See Philof. Tranf. N° 372. or vol. vi. part ii, p. 204. an«l 
N° 402. or vol. vii, part ii. p, 43. Eames's Abr. 
Vol. LI. 
4 f 
<c 
as 
