On Metallic Minerals. 393 



about twenty-five feet above the St. Lawrence and six feet 

 above its natural level. Above these falls as far as the 

 " Furnace Falls," (about twenty-five or thirty miles* hi/ 

 water irora the mouth of the Gannanoijui,) the river is so 

 nearly upon a level that rafts will not descend with the 

 stream unless they be assisted by a favorable wind. The 

 shores of this river are generally low, and I should conceive 

 that much the highest portion of the country, at least on 

 the shores of the Gannanoqui, is on the summit of the 

 granite aggregate, on the left bunk of the river at the 

 " Marble Falls." 



It has been before said that the rock at the Furnace Falls 

 is a granite composed of red felspar, bluish quartz and 

 green hornblende. It forms on the Gannanoqui ; here a 

 cascade of about fourteen feet in height, which gives motion 

 to a flourishing saw and grist mill. I saw close at hand a 

 reddish crystalline marble with points of graphite dissemi- 

 nated, and I heard of large deposits of excellent sandstone 

 and graphite slate in the neighbourhood, but being hurried, 

 the principal object of the visit to these parts, viz, to see 

 the deposits of iron ore, engrossed most of may attention. — 

 One de|)Osit only was seen, that which has been described, 

 but the occurrence of others was mentioned, the localities 

 of which from descrijjtion were not of so favourable a nature 

 as regards the transport of ore. 



At my request Mr. liurrows, an intelligent overseer of 

 works on the Rideau, lately sent me some notes and spe- 

 cimens of rocks found near or on the line of the Rideau 

 Canal from the Cranberry Lake to Kingston Mills. I 

 propose to condeiisx' ihcL-e notes and combine with them 

 niy own observations. 



" <'iii\ Htiiitccn l>\ liiiid, Ml iiiiiiitoii" i\ tin- f(iiii*r M| liiiviMii. 



