wigwam I also shot a very beautiful species of Polyborus, the only one of the kind I obtained on the island.
In an excursion to the southernmost point of the island, Cape Spencer, to the summit of which I ascended, my course lay over a ridge of granite, commencing at St. Joachim's Cove (a small white sandy beach), and extending to the base of Cape Spencer, which is composed of the same rock.
Along the ridge enormous blocks of this rock are scattered about in the wildest confusion; some of these masses were traversed by veins of a dark green, compact greenstone, varying from three inches to three feet in breadth. The summit of Cape Spencer is syenitic greenstone, in broken fragments piled one upon another, and enclosing a crater about two hundred feet in depth; its bottom was occupied by a lake, frozen over on its north side. This crater is about a mile in circumference, its greatest diameter being from north to south. Its highest part is on the west side, forming a very narrow ledge, along which I proceeded to the southernmost precipice overhanging the ocean. This spot commands a fine extensive prospect all round, and the sun shining forth from a clear blue sky rendered every object distinctly visible to a great distance. To the north appeared the snow-capped mountains of Tierra del Fuego, and its many isles. In the S. W. quarter, the Diego Ramirez rocks were faintly delineated above the horizon, like a few small hummocks.
Cape Horn stood boldly forth to the S.E., and the surface of the vast ocean was spread out beneath me to the south. Whilst surveying the scene around me, the solitude of which was broken only by the Polyborus or Fuegian Hawk hovering overhead, my eye suddenly rested upon half a score of the dusky forms of the Fuegians, wending along one of their tracks in the valley beneath in single file, in the direction of their wigwam, at Joachim's Cove; returning in all probability from an excursion in search of limpets along the ledges of
