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F O li M A T 1 U N S 0 V 



were exterminated by the small-pox ; and the land remained in the possession of the 

 Chippewas, until the Missouri Indians made an incursion into the country, and had 

 several battles with them ; after which, the Chippewas left the country, with the 

 exception of ten or twelve families. 



On my way from Mr. M'Derrnott's, by the river, to the colony, I disco- 

 vered, not far from a salt spring, loose slabs of limestone, much of the same 

 appearance and composition as those found on the Rapids. On splitting these open, 

 I disclosed an Orthis, like the 0. plamimbona, a Lept&na (species undetermined), 

 and casts of discoidal bodies, which may be the impressions of Orbiculas. The size 

 and angular form of these slabs indicate that they are not far out of place. The 

 mud on the brink of the river looks, too, like decomposed marlite, such as is often 

 associated with the shell-beds of F. 3, of Wisconsin. The same kind of limestone 

 projects from several points of the shore, near some rapids, a few miles further 

 down the stream. 



At the top of the left bank of the Assiniboin, close to its mouth, I found beneath 

 the soil some large slabs of limestone, similar to those formerly discovered above the 

 Great Rapids of Red River ; but, on closer inspection, it was evident that they were not 

 in place, but had probably served as an underpinning to some house which formerly 

 stood there. I could not learn that there was any quarry in the vicinity whence 

 they could have been brought, but I afterwards observed many large slabs, of the 

 same kind of limestone, about ten miles below, on the immediate bank of Red 

 River, evidently not far out of place. I have no doubt that they were brought from 

 that locality, which is the nearest spot I could find convenient for transportation to 

 the Assiniboin, where limestone fit for such purposes could be procured. 



The mean of five observations, at Upper Fort Garry, at the mouth of the Assiniboin, 

 for latitude, three by meridian altitude of the sun, and two by Polaris, gave for the 

 latitude, 49° 53' 24". Mr. Calhoun, who was attached to Major Long's expedition, 

 in 1823, made it 49° 53' 35"; but, according to a record in the possession of one of 

 the officers of the Fort, Le Froy placed it in latitude 49° 58'. 



As the preparations for the further prosecution of our journey could not be com- 

 pleted for some days after our return from the Pembina Mountain, I took advan- 

 tage of this time to drop down to Lower Fort Garry, for the purpose of making 

 some further geological investigations, in the hope of collecting additional evidence 

 of the age of the limestone of Red River. 



Some eight to ten miles below the mouth of the Assiniboin, the debris of cal- 

 careous rocks are seen on the shore in abundance ; also at various points below this, 

 especially where there are some slight rapids. There can be little doubt that the 

 formation from which they are derived, forms the basis of a large portion of the 

 prairie country of Red River. 



About twenty miles below the mouth of the Assiniboin, near Lower Fort Garry, 

 solid ledges of limestone are exposed, of a light buff colour, sometimes mottled, 

 spotted, or banded with light brown. Immediately opposite the Fort, a considerable 

 amount of rock has been quarried, and used in the construction of the building. 

 In these beds, I succeeded in finding several well-defined and characteristic fossils, 

 sufficient to establish, without the least doubt, the age of the Red River limestones. 



