.'^Peratu 
EARTHaUAK.ES. 14Q 
t "^aal ela.stic vapour, and its discharge, must be 
^ 0 ^.’ require a long space of time ; and if these 
'’OiUifjJ'S to explosions, they must alter the surface of the 
"'^lere they hifppen, destroy the fountains and 
n,„ ’ ^**'1 change the course of its rivers, — results which 
,‘'ntra," “ 
“thes 
'‘foke, 
'•c^io 
truich greater velocity than any heaving of the 
'•tponi-j the sea, caused by the elasticity of generated 
>iot’ would merely produce a gradual swell. 
To tk ^*cted by history and Qbseivation. 
!^e strojf^^ other considerations the Doctor adds, that 
^ Ooc- which ships receive during an earthquake, must 
*'“n by something which can communicate mo- 
such 
an impulsion of the water as resembles a vio- 
tire bottom of a ship, or its striking on a 
be deems the common hypothesis insuffi- 
ijr' ^ddtices several reasons to show that earthquakes 
e.ility electric shocks. To confirm this opinion. 
ki* ■ 
of g/ound is thus previously prepared for that 
^ ^arnp . ■ ■ 
tl V^®> bi several places where tliey have oc- 
w parts, at a small deptlr beneath the 
\\ moist and boggy. Hence he infers, that 
“uiruj ®”^cing other phenomena, either preceding or 
®ttir f(^. ^^ctliquakes, that the weather is usually dry and 
Of before they happen, and that the sur- 
of f ground is thus previously prepared for that 
le 5 g ®®*rical vibration in which they consist ; while, 
Lim^ itA . 
iJi^'kor^ l^S'®us are more subject to earthquakes than the 
Sjf *^ss Qj-’® 'binks is owing to the greater warmth and 
'k(f elect • air, which are qualities so neces- 
tt. It may here be noticed, that, before 
In; ^tk^ljlJ, Jbes of London, in 1749, all vegetation was 
Ygj^®'^"'j’rd ; and it is well known, that electricity 
of bJ’®’‘^tion. Tlie fi-equent and .singular appear- 
by *^®L- au.stral aurorcp, and the variety of 
I'ttiH ®‘'l stat earthquakes are preceded, indicate an 
k 3 >b,t[ • ® the atmosphere ; and the Doctor appre- 
Ptnn''bt‘Ssar’ ® this state of the earth and air, nothing more 
'■tihi'’ ' of^ produce these phenomena, than the ap 
Hr 
,, , /’t)ii-(dectiic cloud, and the discharge of its 
tit *''tte ''p' P‘'t’t of the earth, when in a highly elec- 
tuhg the same way as the discharge from an 
‘■’ucasioas a commotion in the human body 
