266 Dr. Bigsby's Sketch of the Topography 



abounds, both disseminated and in a multitude of slender veins, 

 and particularly about the [ron-works*. 



I have seen a fine specimen of actinolite-slate from the town- 

 ship of Hungerford, on the east of Marmora. 



The great band of primitive rocks on the outlet (to which 

 we have now come) I have repeatedly traversed, both on the 

 water among its almost countless islands, and on its north shore. 

 Of its south shore and vicinity I know nothing but from Mr. 

 Eaton. Unless brought under cultivation lately, it is nearly 

 in a state of nature. 



By far the greater part of the rock here is a gray or reddish- 

 brown gneiss, more or less granular, and containing but little 

 mica and much quartz. It is often the case, that no grain, nor 

 even component part, is distinguishable but on minute inspec- 

 tion. Its direction in all its numerous changes of form is al- 

 ways S. W. Its dip Mr. Maclure states to be S.E. ; but so 

 obscure is the division into layers, and so great the disinte- 

 gration in most places, that I could only satisfy myself of its 

 being at a high angle, and often perpendicular. 



The granular gneiss prevails particularly in the lower part 

 of the outlet, and where the islets are most crowded, as about 

 Wells's and Yeo's Islands. Among the varieties met with in 

 crossing the band between Kingston and Brockville (towns 

 sixty miles apart, situated on its western and eastern limits), 

 are the following : 



The hill of Fort Henry, near Kingston, consists of reddish 

 large-grained gneiss, containing a good deal of hornblende, 

 which prevails in large irregular patches, to the exclusion of 

 other ingredients, as a greenstone. Much of the south-west 

 rampart of Fort Henry rests upon this latter form of rock, 

 close-grained, and sprinkled with a few nests of mica, and fer- 

 ruginous red clouds. The paler gneiss of Cedar Island and 

 its contiguous tongue of land, contains a good deal of epidote, 

 in crystals lining fissures and in veins. At the romantic pass 

 by which Kingston River enters the lake, four miles and a 

 half north-east from the town, the rock abounds very much 



* Here the sienite forms the base of a cliff on the left side of the river, 

 and supports alternating layers three or four feet thick (altogether), of red, 

 gray, and grayish-green argillaceous sandstone, of very fine grain, and smooth 

 to the touch. On this again rests a very compact light-brown limestone, of 

 conchoidal fracture, dim lustre, and often studded with small masses of 

 hyaline calcspar, like the limestone of the Narrows of Lake Simcoe. The 

 cliff is about twenty-five feet high ; but it has in its immediate rear a ridge 

 two hundred feet in height, wholly composed of this limestone, darker 

 however, and coarser, in the upper parts. There are no organic remains 

 here ; but much of the horizontal suture-like divisions which will be after- 

 wards described as occurring strongly marked at Niagara and Kingston. 



in 



