[ 6 79 ] 
the Eaftern Side. And accordingly it was obferved, 
that the rcddifh Bows in the Air, which appeared 
feveral Days before that Earthquake, arofe in the 
Eaft:, and proceeded Weftward. It was obferved, 
after the Earthquake at Smyrna , that the Caftle- 
YValls, which run from Eaft to Weft, were thrown 
down; but thofe from North to South ftood; and 
that the Houfes on Rocks ftood better than thofe 
on the Earth. 
M. de Bnffon relates, that the Vibrations of the 
Earth, in Earthquakes, have commonly been from 
North to South ; as appears by the Motion of the 
Lamps in Churches: Which makes it probable, that, 
tho' the Progrefs of the Earthquake at Smyrna was 
from Weft to Eaft, yet the Vibrations of the Earth 
might be from North to South ; and thereby occalion 
the Falling of the Caftle-Walls, which run from Eaft 
to Weft, but not thofe which run from North to South. 
A probable Argument, that, as the freed: Paflage, fo 
the greateft Explofions were made in the Clefts of 
the Earth which run Eaft and Weft; which would 
make the Vibrations North and South. 
It was obferved, that the Waters turned foul the 
Day before an Earthquake at Bologna in Italy : 
And I was informed, that the Water of fome Wells 
in London turned foul at the time of the Earth- 
quakes. Which was probably occafiond by the 
Afcent of great Plenty of fulphureous Vapours thro’ 
the Earth. 
As to the hollow rumbling Noife, which is ufually 
heard in Earthquakes, it feems not improbable, that 
it may be occasion'd by the great Agitation that the 
eleftrical ethereal Fluid is put into by fo great a Shock 
of a large Mals of Earth. For, if the like Motion of 
a fmali 
