The wonderful cascades of Niagara, where the St.Lawrence leaving Lake Erie plunges 328 feet down into Lake Ontario (which is not much above sea level), remained nearly undiscovered and undescribed until the year 1678, when they were visited by Father Hennepin.

Near the western end of Lake Ontario the two Sulpician missionaries met another Frenchman, Jolliet, who had come down to Lake Superior by way of the Detroit passage, which is really the portion of the St.Lawrence connecting Lake Huron with Lake Erie.

Jolliet told the missionary de Casson of a great tribe in the far west, the Pottawatomies, who had asked for missionaries, and who were of Algonkin stock.

La Salle, on the other hand, was determined to make for the rumoured Ohio River, which lay somewhere to the south-west of Lake Erie.
The two Sulpicians wintered in "the earthly paradise" to the north of Lake Erie, passing a delightful six months there in the amazing abundance of game and fish.

They then met with various disasters to their canoes, and consequently gave up their western journey, passing northwards through Detroit and Lake St.Clair into Lake Huron, and thence to the Jesuit mission station of the Sault Ste.Marie.