e rivers in the Rocky
Mountain region are still almost untouched, though they will some day
find use in manufactures like those of Switzerland.

_The Archean Protaxis._--The broad geological and geographical
relationships of the country have already been outlined, but the more
important sub-divisions may now be taken up with more detail, and for
that purpose five areas may be distinguished, much the largest being the
Archean protaxis, covering about 2,000,000 sq. m. It includes Labrador,
Ungava and most of Quebec on the east, northern Ontario on the south;
and the western boundary runs from Lake-of-the-Woods north-west to the
Arctic Ocean near the mouth of Mackenzie river. The southern parts of
the Arctic islands, especially Banksland, belong to it also. This vast
area, shaped like a broad-limbed V or U, with Hudson Bay in the centre,
is made up chiefly of monotonous and barren Laurentian gneiss and
granite; but scattered through it are important stretches of Keewatin
and Huronian rocks intricately folded as synclines in the gneiss, as
suggested earlier, the bases of ancient mountain ranges. The Keewatin
and Huronian, consisting of greenstones, schists and more or less
metamorphosed sedimentary rocks, are of special interest for their ore
deposits, which include most of the important metals, particularly iron,
nickel, copper and silver. The southern portion of the protaxis is now
being opened up by railways, but the far greater northern part is known
only along the lakes and rivers which are navigable by canoe. Though
once consisting of great mountain ranges there are now no lofty
elevations in the region except along the Atlantic border in Labrador,
where summits of the Nachvak Mountains are said to reach 6000 ft. or
more. In every other part the surface is hilly or mammilated, the harder
rocks, such as granite or greenstone, rising as rounded knobs, or in the
case of schists forming narrow ridges, while the softer parts form
valleys generally floored with lakes. From the summit of any of the
higher hills one sees that the region is really a somewhat dissected
plain, for all the hills rise to about the same level with a uniform
skyline at the horizon. The Archean protaxis is sometimes spoken of as
a plateau, but probably half of it falls below 1000 ft. The lowland part
includes from 100 to 500 m. all round the shore of Hudson Bay, and
extends south-west to the edge of the Palaeozoic rocks on Lake Winnipeg.
Outwards fro