364 Mr D. Milne on Earthquake Shocks felt in Great Britain, 
tired to my room. Thirty minutes had now passed, when 
we were all alarmed by another loud explosion, and the same 
tremulous motion followed, but not so severe. I immediately 
went to the barometer, and examined it minutely. I found 
the mercury which I had left presenting a convex surface, 
now evidently concave, and tending downwards, but no fur- 
ther depression took place. I examined the barometer every 
half hour until 2 o’clock in the morning, when it presented a 
convex surface; and by 10 the next morning, it had risen 
nearly half an inch. The effect in the atmosphere was very 
remarkable, after the first shock. The atmosphere, as I have 
mentioned, was motionless; but before 11 o’clock it blew a 
gale from the east,—in a direct opposite course from which 
the report and the shock came; by 1 o’clock it was again a 
dead calm. Having observed this on the day of the 12th, I 
was particular in making this observation on the night of the 
23d. This gale was also accompanied with rain. The ther- 
mometer stood the whole night at 52°, and no change ap- 
peared to take place in the temperature until next morning, 
when it began to rise. I must remark what appeared most 
extraordinary on the night of the 23d, was those repeated 
explosions which were not accompanied with any tremulous 
motion. I counted twelve or fifteen that night, but I under- 
stood the next morning that twenty had been heard. Those 
explosions I can compare to nothing but a six-pounder fired 
in a coal-pit, the report appearing as if muffled, and some- 
times as if it was discharged in the open air. The excite- 
ment of this phenomenon led me the next day (the 24th) to 
examine the house, the stables, and farm-offices, as I under- 
stood that much damage had been done. I found at the farm- 
offices large quantities of siates had fallen off, and I observed 
there was three times the quantity lying on the west than on 
the east side, and this was also the case at the stables. I also 
found that the chimney-tops and high objects that had been 
moved from the perpendicular, inclined to the west.” 
Clathick, 3 miles east of Comrie—Mr Colquhoun, who was 
at home when the shock occurred, writes that it was felt by 
him “about 10" 10’ v.v. I happened to be in my room on the 
second floor, and was standing. ‘The effect on me was as if 
