CHAPTER XVI.

THE GREAT EXPLORATION.

Grand Portage on American soil--Anxiety about the boundary--David Thompson, astronomer and surveyor--His instructions--By swift canoe--The land of beaver--A dash to the Mandans--Stone Indian House--Fixes the boundary at Pembina--Sources of the Mississippi--A marvellous explorer--Pacific Slope explored--Thompson down the Kootenay and Columbia--Fiery Simon Fraser in New Caledonia--Discovers Fraser River--Sturdy John Stuart--Thompson River--Bourgeois Quesnel--Transcontinental expeditions 133