Mb. Keddie on the Bursting of Crinan Canal. 267 



stated that he had calcxilated dimensions, &c., and found that arrange- 

 ments could readily be made to give rise to oscillations in periods not 

 less than ttt rtrjr of a second, which could therefore be easily shown by 

 Wheatstone's method of the revolving mirror, as he had anticipated 

 might be possible when he first communicated his mathematical 

 investigation to this Society. The barred appearance of each of the 

 photographic images now before the Society would, if the rate of 

 rotation of the mirror, and the distance from it of the plate receiving 

 the impression, were known, be enough to determine the period of the 

 electric oscillation by which they had been produced. He hoped soon 

 to have particular information as to these and other details from Mr. 

 Feddersen, and so be able to make a thorough numerical verification of 

 the theory, which he would not delay to lay before the Society. 



Note on the Bursting of the Reservoirs of Crina7i Canal, shoioing the 

 Power of Running Water. By Mb. William Kedbie. 



The paper commenced by citing some of the few recorded examples 

 in Scotland of the effects of floods in producing permanent changes on 

 the surface of the country. In last session of the Society, a desire 

 was expressed for some facts connected with the bursting of the reservoirs 

 of Crinan Canal, in Argyleshire, on the 2d of February, 1859 ; and 

 although the place should have been visited immediately after the 

 accident, in order to witness the fuU extent of the devastation, its effects 

 were still sufficiently manifest in the month of September, to show the 

 enormous force exerted by the torrent in its descent upon the valley of 

 the canal. By the obliging assistance of Mr. H. D. Graham, an 

 intelligent observer resident in the neighboiu-hood, the following par- 

 ticulars of the catastrophe were obtained, for the illustration of which 

 the same gentleman had made a copy of the original chart of the canal 

 and reservoirs, prepared by Mr. Eennie in 1792, and now in possession 

 of Mr. Fyfe, the present engineer. The highest elevation of the 

 canal is at its centre, about four miles from either extremity, sur- 

 mounted by a series of locks within a space of less than two mUes. 

 Among the hills, overlooking this part of the valley traversed by 

 the canal, there is a chain of natural lochs, serving as reservoirs for 

 supplying the canal. These lochs occupy an elevation of 600 feet (the 

 official report on the disaster says SOO feet) above the sunmiit level of 

 the canal. 'I'lie superficial e.vtent of Camloch is 28 acres, with an 

 average depth of 10 feet; of Duloch, a continuation of Camloch, 5 



