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184 Hand-traverse—Traversing by means of hand-holds only.

Hanging Valley—A tributary valley opening high up on the side of a main valley; often carved out by glacial erosion. It is generally marked by an abrupt step at the mouth, due to the eroding agency having continued its work in the main valley long after it had ceased in the hanging valley.

Height of Land—The watershed between two drainage areas. A crest from which the ground slopes in opposite directions; corresponds to "divide" or "watershed."

Hoodoos—The name given in Western Canada to certain grotesque columns produced by erosion, standing on the slopes of mountains and deep gulches.

Ice-Axe, Ice-Pick—A tough wooden staff, about 3 feet 6 in. long, with an adze-shaped steel head at one and a sharp spike at the other. Opposite the adze, the head is drawn to a point, sometimes set with teeth. It is used to cut steps in steep ice or snow-slopes.

Ice-Fall—That part of a glacier which is much crevassed and broken into séracs through flowing over a precipitous part of its bed.

Knife-edge—A very narrow rock-ridge.

Langthal (German—long valley)—The depression between a moraine and the mountain side, usually filled with snow.

Massif—A central mountain-mass. The dominating part of a range of mountains.

Mittlegrat—A middle edge or ridge, for instance: the rock-edge between two snow-fields or parts of a glacier.

Moraines—The piles of rock, stones and boulder-clay surrounding a glacier and which have been transported by it. Moraines are called Terminal, Lateral, and Medial, according to location: at the end, the sides, or in the middle of a glacier. Lateral moraines are generally and medial moraines are often piled hundreds of feet above the glacier. This is owing to the fact that they consist of a cone of ice which has not melted proportionately with the main body of the glacier, because of the protection afforded by the thick veneer of rock, boulders and clay.

Moulin—A nearly vertical shaft or well cut through a glacier by a stream flowing on the ice.

Névé—The accumulated snow forming the source of a glacier; corresponds to "snow-field" or "firn."

Nunatak—A crest or ridge or rock appearing above the surface of an ice-field or glacier.

Piedmont—A term applied to a compound type of glacier made up of a series of glaciers of the common alpine type, all of co-ordinate importance, which coalesce laterally but retain their individuality from névé to nose. The Asulkan Glacier of the Selkirks and the Wenkchemna and Horseshoe Glaciers of the Main Range are examples.

Pothole—A cavity more or less cylindrical in form, varying from a few inches to many feet in depth and diameter, made by an eddying current of water which causes stones and other material to revolve and thus wear away the surface with which they come in contact.

Red Snow (Protococcus nivalis)—A unicellular plant, an alga, related to the sea-weeds, and belonging to the lowest form of plant