-115 



THE EAETHQUAKE OP OCTOBER 6th, 1863. 



On the moming of Tuesday, the 6th of October, 1863, at 

 about 20 minutes past 3 o'clock, Greeawich time, the sky being 

 then free from clouds, and the air cold, calm, and clear, a very 

 extraordinary sound was suddenly heard approaching with as- 

 tonishing rapidity from the Westward. 



This sound, which appeared to consist of a rapid succession 

 of detonations, ■« as accompanied by a tremor of the ground which, 

 made the windows rattle in their frames as in a gale of wind. 



Then came a very considerable lift of the ground — the true 

 earthquake wave — and, with the shock, a crash of subterranean 

 thunder, resembling the firing of a battery of heavy guns under- 

 foot. Immediately afterwards the sound was heard dying away 

 in the distance. 



According to Daubeny, all earthquake movements, when 

 they are anything more than mere tremors, may be divided into 

 three kinds ; — "the undulatory, the succussive, and the vorticose." 



" Of these three kinds of earthquake shocks, the first is the 

 most common and the most harmless. From the second, that of 

 succussion, more is to be apprehended ; but the vorticose move- 

 ment is the one which, has been felt in the most violent and dis- 

 astrous catastrophies on record." (Daubeny on volcanoes, c. 32.) 



The earthquake of 1863 was one of the first kind ; the un- 

 dulation "proceeded onward in a uniform direction ; " * and thus 

 although the shock, in this neighbourhood, at least, was very 

 considerable, no serious mischief followed the movement. 



* Daubenv. 



