But he had received a memoir from General Cass, Governor of Michigan, proposing to explore the sources of the Mississippi, through the Lakes, and suggesting that a naturalist, conversant with mineralogy, should accompany him, to inquire into the supposed value of the Lake Superior copper mines.

He tendered me the place, and stated the compensation.

The latter was small, but the situation appeared to me to be one which was not to be overlooked.

I accepted it.

It seemed to be the bottom step in a ladder which I ought to climb.