termine the latitude and longitude of the places visited. The party set out from a post on the Mississippi about five hundred miles (by river) above the mouth of the Mizouri and traveled nearly four hundred miles in a northerly direction, over rugged hills and broad plains, narrow prairies and extensive forests, first of hard woods and later of great pines. At last they came to the shore of a lake so vast that it seemed like a sea. Near the lake they found many outcroppings of metallic copper and copper ore, with indications that much greater quantities could he obtained by mining.
The Indians informed the explorers that another great lake lay off to the southeast of the copper mines, on which they could, by going southward, reach a point less than six days' journey from the Mississippi. It was determined that on reaching this lake a few of the party should go by canoes as far as possible, leaving the rest of the party to return by nearly the same route as they came.
Crossing the peninsula separating the two great lakes, a party of five white men, including the mathematician, and two Indian guides, embarked in birch canoes and set out southward along the shore of the great and solitary
