362 DR. CHARLES DAVISON ON THE [Aug. I907, 



24. The Ochil Earthquakes of September 1900 to April 1907. 

 By Charles Davison, Sc.D., F.G.S. (Read June 19th, 

 1907.) 



[Plate XXVI- Map.] 



I. Introduction. 



During the last two years, the district on the south side of the 

 Ochil Hills, known as the ' Hillsfoot District/ has been visited by a 

 number of slight earthquakes, which, in their nature and frequency, 

 bear some resemblance to those which made the name of Comrie so 

 well-known in the preceding century. The stronger shocks are 

 briefly described in the local and other newspapers; but the majority 

 would no doubt have escaped record, had it not been for the interest 

 taken in them by several gentlemen who reside in the district and 

 who have kindly communicated to me the results of their observa- 

 tions. My thanks are especially due to Mr. W. H. Lindsay and 

 Mr. T. J. H. Drysdale, of Menstrie ; Mr. J. Dempster, of Airthrey ; 

 and Mr. Tyndall B. Johnstone, of Red Carr (Blairlogie), for many 

 valuable lists of shocks. To Mr. Lindsay I am also indebted for 

 introductions to several other observers, whose frequent notices have 

 added much to the completeness of the record — to the Rev. J. Boyd, 

 of Menstrie ; Dr. W. L. Cunningham, of Alva ; the Rev. Menzies 

 Pergusson, of Logie ; Mr. J, M. Morries, D.L., J.P., of Gogar ; 

 Mr. Alexander Scott, Jun., of Tillicoultry ; Mr. R. D. Taylor, of 

 Blairlogie ; and the Rev. J. Williamson, of Alva. I have also to 

 acknowledge the courtesy with which many observers in other 

 places replied to my enquiries about the more prominent shocks. 1 



The list of earthquakes in the Ochil district before the year 1900 

 is evidently very incomplete. So far as I can ascertain, it includes 

 only five shocks, although others may possibly have been referred to 

 the well-known Comrie centre. They are as follows : 



1736, April 30th and May 1st. ' At One this Morning [May 1st], and at 

 Noon the preceeding Day, was a terrible Earthquake along the Ochil Hills in 

 Scotland, which rent several Houses, and put the people to flight, it was accom- 

 panied with a great Noise under Ground.' 2 



1842, July 10th. A shock was felt at Dunblane between 11 a.m. and noon. 3 



1872, August 8th. At 4.8 or 4.10 p.m., a shock, of intensity 6, was felt at 

 Braco, Eanbuck, Dunblane, Bridge of Allan, and Stirling. Towards the north, 

 it was felt as far as St. Fillans, Comrie, Glen Lednock, and Crieff. A heavy 

 rumbling sound was followed immediately by a wave and then by a double 

 vibration, the whole duration being from 3 to 4 seconds. This earthquake 

 must have resembled closely the principal shock of the recent series, that of 

 September 21st, 1905 (see PI. XXVI). 4 



1881, January 12th. A smart shock was felt at Bridge of Allan and Menstrie 

 at about 7 a.m. 5 



1 The expenses of the investigation of these earthquakes were defrayed from 

 a grant received from the Government Research-Fund. 



2 ' The Gentleman's Magazine ' vol. vi (for 1736) p. 289. 



3 Brit. Assoc. Eep. 1854 (Liverpool) p. 323. 



4 Brit. Assoc. Rep. 1873 (Bradford) pp. 194-97 ; Annual Register for the 

 Year 1872, pt. ii, p. 65 ; & ' Alloa Journal ' August 10th, 1872. 



5 ' Nature ' vol. xxiii (1881) p. 275 ; & 'Alloa Advertiser' January 22nd, 1881. 



