in a Canadian winter. While a thick covering of snow retains heat in the earth for the protection of vegetation, and when the fish retire to the shelter of the deep water in the ice-covered lakes, the open area at the rapids affords the principal outlet for radiation,-which increases with the intensity of the frost-and at these points an almost constant congelation in the form of "anchor ice" upon the bed of the stream, sets free an additional supply of latent heat.

Another peculiarity of the Canadian navigation is its great directness. From the Straits of Belle Isle to the head of Lake Erie, the St. Lawrence affords a navigation almost upon an air-line; and from Montreal to the western extremity of Lake Superior, the Ottawa gives a route nearly direct. The Mississippi and many of its tributaries, on the other hand, double the air-line distance between their cities, and oppose an almost uniform current to ascending craft. While batteaux could be dragged up the rapids and sail up the St. Lawrence in ten or twelve days from Montreal to Lake Ontario, and there transfer their cargoes to schooners, it required four months to pole a keel-boat up the Mississippi from New Orleans to St. Louis; and it was not until the successful invention of the steamboat that the western rivers could be commercially navigated, and thus have their fertile valleys opened to the immigrant.

The river St. Lawrence-that great aorta of the province of Canada, which drains an area of half a million of square miles, and opens a highway for ocean borne vessels from the Atlantic fully two thousand miles into the interior, or more than half-way across the continent,-has ever been a base-line of operations in those struggles, both military and commercial, which have taken place between the rival races and rival offshoots from the same race in the New World. Its two most important branches, the Ottawa and the Richelieu, were, on account of their great directness towards the West and South, their slack-water, and the greater de

pression in their valleys, favorite thoroughfares of the Algonquin and the Iroquois, and these characteristics are none the less important to the commercial requirements of our own time. The Appalachian chain of mountains, sweeping the curve of a great circle of the earth from the Gulf of Mexico to the St. Lawrence, is cleft to the ocean level at the Hudson River, and only there. Almost in a direct line north of this river, and apparently a continuation of the same fissure in the chain, Lake Champlain discharges in an opposite direction, into the St. Lawrence, by means of the river Richelieu. This lake is only eighty feet above tide water, and the summit level of the canal connecting it with the Hudson is only fifty-five feet higher. A subsidence, therefore, of only one hundred and fifty feet, along the line of this valley, would open salt-water navigation between Montreal and New York, and make an island of New England and the Lower Colonies.

PROGRESS OF NAVIGATION.

The progressive stages in the navigation of the northern rivers are

The Bark Canoe;

The Batteau;

The Barge or Durham Boat;

The Horse-boat;

The Steamboat;

To which-for the lakes-may be added every description sail-craft required in ocean navigation.

The Bark Canoe.-This primitive vessel of the northern aborigines is one of the most useful and economical vehicles for travel and light traffic upon a broken and sheltered navigation which can possibly be devised. Every attempt to improve upon it, by substitution of tin or otherwise, has failed, and it is to this day the favorite craft of the lumberman for ascending or descending the tributaries of the Ot

tawa, where no summer roads are found. In size they range between nine and thirty feet-one and a half to five fathoms, as the measurement is usually given. The smaller size will only carry one person, with a small stock of food or necessaries to trim the ship; and as one person can easily carry it, a considerable journey with numerous portages may be made solus wherever there is a foot of water in the stream. The larger canoes will carry twenty-five to thirty men, or a cargo of three tons, and when loaded draw two feet of water. The frame-work consists of numerous single ribs or laths, bent like an ox-bow, and terminating in the gunwales; all which, with the bow and stern-post, are made of white cedar (Thuya occidentalis,) the lightest and most durable wood our forest affords. The few bars which maintain the opposite gunwales in situ are of maple, elm, or ash-cedar not being strong enough-but they are attached, through holes bored in their ends, by a seizing of young roots, (instead of being framed in,) so that they can readily be replaced. The sheathing is the bark of the white birch(Betulu papyracea,) more durable than the cedar itself, (although that lasts as long as the owner,) sewed together and lashed to the gunwale with the fine, tough, and durable filaments which form the young roots of the spruce, and which are prepared by boiling. The seams are payed with a pitch composed of resin and tallow, which makes them water-tight; but often the raw gum of the forest tree is used. Thus it will be seen that with the exception of the cross-bars, so easily replaced, there is no perishable wood in the bark canoe; and they are lighter for their tonnage than any other craft of equal strength. Being very elastic they will stand a good deal of rubbing on boulders or waterworn rocks not sharp enough to cut them through; and if damaged the adjoining forest affords the means of repair. The largest canoe requires a crew of six to eight men, but can be carried by one-half this number; and it is only with

the larger sizes that more than one of the crew is needed to carry the vessel over the portages. At night the canoe inverted affords shelter from rain and dew.

The bark of the birch-tree forms the covering for the wigwam or hunters' camp-gives utensils in which flour is kneaded and water boiled-is the papyrus on which the Indian pioneer sketches with native plumbago hieroglyphics (which are left in cleft sticks at the portage landing) for the guidance of his following tribe-and makes the resinous torch for lighting the portage, the camp, or the night-fisher's spear; while the green wood from which it is stripped burns as readily on the camp-fire as the dry of any other

tree.

The Batteau.-When the extent and regularity of the traffic called for some more improved means of transport, the batteau-a large, flat-bottomed skiff, sharp at both ends, about forty feet long and six to eight feet wide in the middle, and capable of carrying about five tons-was substituted. Sometimes they were confined to a particular reach of water; in other places they were, with the aid of ropes and windlasses, men and oxen, dragged up the shallow rapids; or were unloaded and carted across the portages. They were provided with masts and lug-sails with about fifteen feet hoist, an anchor, four oars, and six setting-poles shod with iron, and a crew of four men and a pilot. With forty barrels of flour on board they drew only twenty inches of water. Their great merit was in their entire adaptation to the work and to all conditions of the route. They could not be capsized in the excitement of a rapid, while their light draft enabled them to creep up along shore; nor could the flat bottoms be easily damaged on the water-worn rocks. When coasting along the shore of the great lakes, if the sea became too rough they could be hauled up and inverted to afford shelter like a canoe. Though by no means models their light draft and displace

ment and their sharp bows made them tolerable sailers and not difficult to row.

In the last century the batteau was used, almost exclusively, on the inland waters. Although ships of four hundred tons then came up once a year to Montreal, and although there were, as early as 1795, three merchant vessels on Lake Ontario of from sixty to one hundred tons, which made eleven voyages in the year, (besides the six king's vessels which carried the mails, troops, and passengers,) the batteau was still used for purposes of travel and light transport from Quebec to York. Passengers from Montreal went down with the current to Quebec in a batteau having a section covered with cloth stretched over hoops, forming a sort of cabin; but came up by land to save time. From Montreal westward there was no choice; the passengers were obliged to camp on shore at night, and shot over the adjoining woods while the crew were toiling up the rapids. This state of things continued until the introduction of the steamboat and the completion of the land road.

The Durham Boat was introduced after the war of 1812 by the Americans, and adopted to a considerable extent by the Canadians, the object being to combine the light draft of the batteau with better sailing qualities and greater tonnage capacity. They were flat-bottomed barges with keel and center-board, and with rounded bows; eighty to ninety feet long and nine to ten feet beam, with a capacity about ten times that of a batteau, or about 350 barrels of flour, down; but, in consequence of the rapids and want of back freight, they brought only about eight tons up, on the average. The commencement of agricultural exports and consequent increase in the downward tonnage, after the war, called these boats into existence; for, though unable to carry a full load up the stream, they could bring up enough to meet the demands of the route,-the proportions between the down and up freights having materially changed from