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ON EARTHQUAKES IN GREAT BRITAIN. 121 
wider field of induction. The Committee will endeavour to get this defect 
supplied in the observations of the ensuing year. 
The first shock at Comrie on the 24th of September 1842, though by no 
means violent, was well marked by the instruments. The inverted pendulum 
placed in the steeple there (and which is ten feet long) had its head thrown 
to the north-west about one-eighth of an inch, indicating that its base had 
been suddenly moved thus much to the south-east. Another instrument, on 
the principle of the common pendulum, about four feet long, had its lower 
extremity thrown also one-eighth of an inch to the westward, indicating that 
its point of suspension had been suddenly pushed thus much eastward. Two 
other instruments, constructed so as to be affected by vertical concussions, 
indicated an upward heave of the ground to the extent of th of an inch. 
The instruments were affected on other two occasions, as needs in the re- 
gister, but not in any very marked degree. Their indications entirely accord 
with the inference derived from the experience of shocks in previous years,— 
that the point from which they emanate is west-north-west from Comrie, and 
distant from it about a mile, or a little more. 
The Committee will next notice the other places in Great Britain where 
during the last year they have learned that shocks have been felt. They will 
mention them in chronological order :— 
August 19, 1842. At Pitlochry, between Dunkeld and Blair, about 8 p.m., 
three shocks were felt. It was remarked that the night was warm and sultry, 
with a drizzling rain, and that at midnight the thermometer stood at the un- 
usual height of 72°. 
August 22, 1842. A shock was felt in North Wales, and extended through 
the whole of Anglesea. The south-east portion of that island was most affected. 
February 25, 1843. At Oban and Lochgilphead, in Argyleshire, as also in 
the intervening district, a shock was felt about 8 p.m. A person who felt this 
shock near Oban, described it to one of the Committee as producing a motion 
“such as one feels when standing near a heavy cart passing on a hard road 
made on a deep mossy bottom,—a sort of heaving and trembling at the same 
time.” In a paragraph which appeared in the newspapers, it was stated that 
a person near Oban observed a flash of lightning about the time of the shock. 
March 3, 1843. At Lochgilphead a shock was again felt about 8" 40™ p.m. 
It was attended by the usual trembling and subterranean noise. It lasted from 
thirty to forty seconds. 
March 10, 1843. Through the district to the north-east of Manchester an 
earthquake was felt about 8 a.m. Its most violent action was said to have 
been in the chain of hills separating Yorkshire and Lancashire. 
March 17, 1843. About | a.m., the same district was again affected by a 
shock, but which on this oceasion had a much wider range. It was felt 
simultaneously in Lancashire, Cumberland, Dumfriesshire, Isle of Man, 
Belfast, and even in the islands of Jersey and Guernsey. It does not appear 
to have been felt in the intervening district of the aide and south-east of 
England. 
This shock was accompanied by a noise which is dieseraben as resembling 
the hissing of steam or the rushing of wind. The ground also trembled, and 
in some places heaved. Even at Belfast and its neighbourhood, where the 
effects produced have been reported on by Mr. Bryce, a member of the Com- 
mittee, the particular phenomenon now adverted to was perceived. Mr. Bryce 
says, “that the motion was that of a ship in a heavy swell, and the feeling 
was given that the room and bed were rolling over.” By another it is de- 
scribed as like “that rolling motion of a ship which induces nausea ;” and 
this individual actually experienced that sensation in a slight degree. Another 
