ON EARTHQUAKES IN GREAT BRITAIN. 95 



1. On the 26th of July 1841 (as Mr. Macfarlane reports), a shock oc- 

 curred, which is noticed in the register. The inverted pendulum set in the 

 steeple of Comrie parish church was thrown about half an inch to the west, 

 apparently indicating a horizontal movement of the ground as much towards 

 the east. Another instrument, invented by Mr. Macfarlane himself, on the 

 principle of the common pendulum, and kept at his own house, about 150 

 yards from the church, had vibrated in a direction due east and west. On 

 this occasion an itpioard heave of the ground, to the extent of half an inch, 

 was also indicated by two instruments, one of them being a horizontal bar, 

 of the nature before described. 



2. The next shock by which the instruments were affected, occurred on 

 the 30th of July 1841. Mr. Macfarlane reports that the two inverted pen- 

 dulums in his house vibrated to the extent of half an inch, and in a direction 

 south and north, which is different from previous indications. At Tomperran 

 (about a mile and a half east of Comrie), an instrument on the principle of 

 the common pendulum vibrated east and west. The instruments for showing 

 any vertical movement were but slightly affected. 



Notwithstanding the slight nature of the effects of this shock on the in- 

 struments, Mr. Macfarlane reports that it was very severe, though not so 

 violent as the one which occurred in October 1839. Reckoning this former 

 one at 10, he says the shock of July 30, 1841, may be reckoned 8. He adds, 

 that " it was distinctly double, the latter part, if anything, more violent than 

 the first : the noise and shake awful, at least I felt them so in the house, 

 and those out of doors gave the same account. It is difficult to account for 

 the smallness of its effects on the instruments. Perhaps the vibrations of the 

 ground, though violent, were short and frequent, and thereby interrupted the 

 natural swing of the pendulums. I recollect some person, on the occurrence of 

 one of the former severe earthquakes, describes his feelings as if on horseback, 

 when the animal shook itself. Somewhat such were my impressions on the 

 30th, even before I had looked at the instruments. It is said here that there 

 were twelve shocks that day. I felt nine myself; there was one about 

 8 a.m., pretty smart, and none else till the great one about 2 \ p.m. Imme- 

 diately after it there were two or three slight shocks, and about an hour 

 afterwards a loud one, &c. The weather was cold and inclined to stormy 

 about the time of the severe shock, and for a day or two before and after." 



In a subsequent letter, dated August 9, 1841, by which time Mr. Macfar- 

 lane had visited all the places in and near Comrie affected by the shock, he 

 gives some details, which it may not be out of place here to notice. " A 

 house at Garrickrow (about two miles west of Comrie) was so severely 

 handled that three out of four chimney-tops will require to be rebuilt or re- 

 paired, and there is a rent in the west gable of the house. A man from 

 Comrie, who happened to be working at the time on the hill behind, de- 

 scribes the shock as awful indeed ; and he says the trees around him were so 

 much agitated that he thought they would have been torn out of the roots, but 

 he cannot remember exactly in what direction they waved, but thinks it was 

 east and west. The wall of one of the houses of Ross (the neat suburb of 

 our city) was rent, and the miller's house (you '11 recollect it), in spite of its 

 numerous abutments, has had its rents much enlarged. This shock, I learn, 

 has been felt as far east, at least, as Newburgh, about thirty-eight miles from 

 Garrickrow ; as far to the west as Dalmally, the distance of which I do not 

 exactly know (but probably it may be about the same); as far north as Glen- 

 lion, thirty miles ; and as far south as Alloa and Stirling, twenty to thirty 

 miles. 



" I have seen several of the shattered buildings; one of the chimney-tops 



