1848.

YUKON RIVER.

227

to issue from a lake, which also gives origin to a still smaller stream, bearing likewise the appellation of the Rat, and taking an opposite course to join the western branch of the Mackenzie. The Western Rat River is an affluent of a considerable stream, named the Porcupine, which, running to the westsouth-west for two hundred and thirty miles, enters the Yukon, a river emulating the Mackenzie in size, and flowing parallel to it, but on the western side of the Rocky Mountains. Of the country watered by this great river, and its inhabitants, I shall take occasion to speak hereafter.

The eastern channel of the delta of the Mackenzie is also flanked by a ridge, named the Reindeer Hills, which I consider to be a prolongation of the spur that the Mackenzie crosses at the "Narrows." They are not so rugged or peaked in their outline as the Richardson chain, or the spurs which the Mackenzie passes through higher up; and their general height does not appear to exceed seven or eight hundred feet.

Having finished the operations at the cache, we resumed the voyage, and, retracing our way for a few miles, entered the eastern channel of the delta, and pursued it until seven in the evening, when we encamped, about twenty-two miles below Point Separation. The banks of the river here, and the numerous islands, are well wooded.

The

balsam poplars rise to the height of twenty feet, and the white spruces to forty or fifty. Numbers of sand martens burrow in the banks. These birds winter in Florida. Mr. Audubon informs us, that in Louisiana they begin to breed in March, and rear two or three broods in a season. In the middle states their breeding-time commences a month later; and in Newfoundland and Labrador it rarely takes place before the beginning of June. Near the mouth of the Mackenzie, the banks are scarcely thawed enough to admit of excavation by the feeble instruments of this bird before the end of June; and in the beginning of September, the frosts prostrating the insects on which the martens feed, they and their young broods must wing their way southwards. I was unable to procure a specimen of this marten, though it breeds in multitudes along the whole course of the Mackenzie, and am therefore unable to decide whether it is the Hirundo riparia or Hirundo serripennis of Audubon; but from its nearly even tail, I rather incline to think it may be the latter; and if so, it may not be the same species which breeds in the southern states. The sand marten was first seen by us on the 28th of May, as we were descending the River Winipeg, near the 50th parallel, and we know, from our observations in 1826, that it reaches the delta of the Mackenzie by the beginning of July; affording thus an index to the progress of spring

1848.

MASS OF TRAP.

229

in different latitudes. On the Winipeg it was accompanied by the purple swift (Progne purpurea), whose northern limit we did not ascertain.

We resumed our voyage at three in the morning on the 1st of August, and when we landed to cook breakfast, saw some recent footmarks of Eskimos. As these people are employed at this time of the year, in hunting the rein-deer on the hills which we were skirting, we were in constant expectation of seeing some of their parties. The Rein-deer Hills, as viewed from the eastern channel, seem to be an even-backed range; but when examined with the telescope, they are seen to consist of many small, oblong, rocky eminences, apparently of limestone, and are sparingly wooded. In the course of the morning we crossed the mouths of three pretty large affluents, coming in from the hills, and also two cross canals, dividing M'Gillivray Island into three sections.

About thirty-five miles from Point Separation, or in latitude 68° 10′ N., the channel washes the foot of a low dome-shaped bluff, in which the intrusion

TRAP

SANDSTONE

LIME

STONE

of a mass of trap, which now forms the top of the hill, has tilted up a bed of limestone, and separated it from one of sandstone.

In the afternoon we passed another considerable affluent from the hills in lat. 68° 18' N.; some hours later, another one of less size; and very soon afterwards crossed a channel which bounds Harrison Island on the south. This island, like M'Gillivray's, is divided into several portions by minor creeks. The boats were under sail all the afternoon, and must have been observed, about 5 o'clock, by the hunting-parties of the Eskimos, for at that time we noticed a line of six or eight signal smokes, raised in succession along the hills, and speedily extinguished again. As the Eskimos use fire-wood very sparingly for cooking, and, like the Indians generally, burn only dry wood which emits but little vapour, we knew that the smokes we saw were intended to spread the intelligence of the arrival of strangers in the country, and therefore that we might expect to find a considerable body assembled on some part of the river to meet us. In the evening we landed to cook supper, and re-embarked to continue under sail all night, with a very light breeze; our progress was, however, slow, owing to the uncertain eddies and currents, produced by the junction of the several cross-channels. At midnight we passed the creek which bounds Harrison Island on the north, in 68° 37′ N. Here several

1848.

VEGETATION.

231

gently swelling elevations interpose between the river and the main ridge of the Rein-deer Hills. The valleys and borders of the river are well wooded, but the summits of the eminences present only scattered spruce firs, with stunted tops and widely spreading depressed lower branches. The canoebirch (Betula papyracea) is frequent, and the trees we measured were about five inches in diameter. The Populus balsamifera and Alnus viridis grow to the height of twenty feet, and the Salix speciosa to upwards of twelve. The Ribes rubrum, Rubus chamamorus, and Vaccinium vitis idea, bore at this time ripe fruit. The Rosa blanda, Kalmia glauca, Nardosmia palmata, and Lupinus perennis, were also observed flourishing in this high latitude, together with several other plants which extend to the sea-coast. Among the birds, we saw the great tern (Sterna cayana), the Coryle alcyon, and Scolecophagus ferrugineus, the latter in flocks.

August 2d. For five or six hours this morning we ran past the ends of successive ridges separated by narrow valleys. The diagram gives the outlines of one of these spurs seen on the southern flank. It is about three hundred feet high, and its acclivities are furrowed deeply, producing conical eminences which are impressed with minor furrows. The vegetation is scanty; a few small white spruces straggle up the sides; and the soil, where it is