698 Earthquakes and Electricity . [December, 
throw perhaps a few gleams of light along a short distance 
of a path that may possibly, if patiently explored, eventu- 
ally lead to the desired goal. 
In a very interesting article on “ Earthquakes ; their 
Cause and Origin,” that appeared in the “ Quarterly Review” 
for July, 1881, the author (whose name is unknown to the 
present writer) mentions the following theories as the prin- 
cipal ones that have from time to time been enunciated as 
probable causes of these phenomena : — 
1. Water expanding into steam on coming into contact 
with subterranean lava. 
2. Chemical changes or combinations within the earth. 
3. The shrinking and cooling of the earth’s crust. 
4. Rupture by tension. 
5. Collision between solids and a liquid. 
6. The passage of a wave of elastic compression causing 
each particle of earth to perform a vibratory move- 
ment. 
7. An incomplete effort to establish a volcano. 
But in the opinion of the reviewer the cause of earth- 
quakes was attributed to electricity, and his paper contained 
strong arguments in favour of this idea, though no allusions 
were made to the writings of previous advocates of the elec- 
trical theory. The present writer is equally impressed with 
the belief that electricity is the true source of earthquake 
phenomena, and he had already published his views on the 
matter (in connection with thunderstorms) before he was 
aware of the existence of another worker in the same field ; 
and he now proposes to submit a slight historical notice of 
some of the suggestions that have at different times been 
advanced in connection with the association between earth- 
quakes and electricity. 
The most ancient allusions to the subject are probably 
those contained in the Scriptures. After the arrival of the 
children of Israel in the wilderness at the foot of Mount 
Sinai, on their journey from Egypt to Canaan, “ it came to 
pass on the third day in the morning that there were thun- 
ders and lightnings and a thick cloud upon the Mount, 
and the voice of the trumpet exceeding loud ; so that all 
the people that was in the camp trembled. And Moses 
brought forth the people out of the camp to meet with God ; 
and they stood at the nether part of the Mount. And 
Mount Sinai was altogether on a smoke, because the Lord 
descended upon it in fire ; and the smoke thereof ascended 
as the smoke of a furnace, and the whole Mount quaked 
