26 The Ottawa Naturalist. [April 



and which join a short distance above the village of Portage du 

 Fort. 



Of these two channels the south or Roche Fendu, is very 

 rough and rocky. The north channel from Le Passe around the 

 north end of the island and down to Bryson, flows for the most 

 part of the distance through great beds of sand which show on 

 both sides of the river but are very largely developed on the 

 island, especially on the northwest portion. 



Below the Chenaux Rapids the Chats Lake forms the river 

 and extends down to the head of the Chats rapids and Falls about 

 three miles east of the town of Arnprior. The shore on the north 

 side opposite Sand Point and thence to a point opposite the mouth 

 of the Bonnechere River is largely drift covered, and this feature 

 is well seen at Norway Bay where great banks of sand form the 

 shore line for some distance. Inland also these deposits are 

 largely developed to the east of Shawville, where they overlie a 

 great thickness of clay, which extends northward to the main 

 ridge of crystalline rocks. 



The Chats Falls are caused by a large dyke of reddish 

 granite which cuts across the crystalline limestone of the Arnprior 

 and White Lake belt, here several miles in width. The falls 

 are among the most beautiful on the river, extending across the 

 whole breadth of the stream which is here about two m.iles 

 in width. The total rise from the foot of the falls to the waters of 

 Chats Lake is about fifty feet. 



Just below the Chats Falls on the south side is the village of 

 Fitzroy Harbour, It is built on a clay blufT about forty feet 

 in height and this rests on the Calciferous dolomite, which in turn 

 reposes on the gneiss and crystalline limestone at the foot of the 

 falls. These newer rocks are seen on both sides of the river. 



The Carp river enters the Ottawa a short distance below the 

 village, and has a course of about twenty miles. It also flows 

 westerly against the general course of the Ottawa in a depression 

 through the northern part of the townships of Huntley and 

 Fitzroy and is on the whole a very sluggish stream. About four 

 miles above its mouth there is a rapid formed by a ridge of granite. 

 Elsewhere the bed of the stream is a clay flat, in places very 

 marshy, to its source, which is in the northern part of the township 

 of Goulbourn. 



