St. Maurice Expedition. 9 



and on the nortli shore near Cape le Blanc, where a small 

 deposit of clay again makes its appearance, nothing but a 

 light silccious sand is met with, resting to various depths 

 on the primitive rock, as far as VVemontachinque. 



In some places, particularly at the lower Caribou Moun- 

 taui, and immediately above Rat River, the sand hills are 

 from eighty to upwards of one Imndred feet in height. 



On the west side of Lake Manjeamagouth, a bed of clay 

 is again found stretching towards the south; and this 

 clayey deposit is fallen in with on the middle and lower 

 parts of the River aux Lievres. 



The sienitic rock which is found as low as the Grais 

 Rapids, and probably extending below the Gabelle, con- 

 tains a little black mica, but not sufficient to alter the 

 character of the rock. On the shores arc immense bowl- 

 ders of (piartz, containing abundance of common garnet, 

 in some respects similar to the manganesian garnet, and 

 possibly owing their violaceous hue to the presence of 

 oxide of manganise. 



At the junction of the Shewanahegan with the St. 

 Maurice, we observe that remarkable subsidence of the 

 land which forms the extensive basin, receiving the waters 

 of the St. Maurice and Shewanahegan in one blended 

 stream. On the north side of the basin is the almost jjcrpen- 

 dicular precipice of sicnite, down which rush the waters of 

 the St. Maurice in two separate falls, the river being divided 

 by an Island nearly a (puirter of a mile in Midth. 'I'hese 

 fallh are cfctimated at one hundred and fifty feet in height. 

 At the fool of the precipice lyr confusedly hea|)ed together 

 thu ilcbris (if ilic rock, and ojipositu on tla- north shore are 

 large blocks of a similar garnet-rock, as that before jles- 

 cribcd at the Rajud (Jrais ; exce|)t that ihcy contain a very 



