OCT. — DEC. 1856.] 
Scientific Inielligence. 
109 
IX. Scie7itijic Intelligence. 
[The following letters regar ling Earthquakes, lately observed at Travancore, 
are extracted from the Madras Athmceum '] 
Sir, — Peihaps the following account of the Earthquake observ- 
ed in Travancore on the morning of Monday the 11th instant may 
interest some of your readers ^ 
The assistant in the Tuevandrum observatory having the watch 
on the morning referred to, was entering an observation when he 
heard a low rumbling sound which he thought at first was distant 
thunder towards the north-east; in about three seconds the raft- 
ers of the building began to creak, the windows to rattle and a 
mirror resting on the table to shake : he immediately looked at 
the clock and found the time 5 h. 53 m. 30 s. which, allowing for 
the known clock error, would give the mean Trevandrum time of 
the commencement of the sound 5 h. 51 m. 25 s. He then went 
out to look towards the north-east and immediately thereafter the 
sound ceased with a louder " bom" ; on looking again at the clock 
the time by it was 5 h. 54 m. and he estimated the duration of 
noise and shock at nearly twenty seconds. He now examined the 
magnetical instruments, but could perceive neither vibration nor 
change of mean position. It is not impossible however that the 
magnets might have had swinging or dancing motions without be- 
ing remarked by the observer, as vibrations round a vertical axis 
only are noted. An examination by myself since, of the observa- 
tions made before and after the shock, confirms the fact of the 
steadiness of all the magnets ; neither did I find any thing remark- 
able in the state of the atmosphere. The velocity of the wind from 
the north-west was nearly as usual at the same hour; the sky was 
nine-tenths clouded, the clouds moving from north-west ; the 
temperature of the air was nearly 73®, the maximum temperature 
of the day being nearly 78^. 
A lady living near the observatory was awoke by a low rumbling, 
puffing noise, which terminated by a stifxcd explosion, as if under 
