We were able to enjoy this delightful variety of esculents for more than a month. Then, the little tubercles of the fern became hollow and horny, and the stems themselves grew as hard as wood; while the nettles, armed with a long white beard, presented only a menacing and awful aspect. Later in the year, when the season was more advanced, the perfumed strawberry of the mountain and the white mushroom of the valley, became invaluable substitutes for fern and nettle. But we had to wait a long time for these luxuries, the cold in these countries being of protracted duration, and the vegetation, of consequence, exceedingly late. Throughout June there is snow still falling, and the wind is so cold that you cannot, without imprudence, throw aside your fur coats. With the first days of July, the warmth of the sun begins to be felt, and the rain falls in heavy showers; no sooner has the sky cleared up, than a warm vapour rises from the earth, in surprising abundance. You see it first skimming the surface of the valleys and the low hills; then it condenses, and oscillates about somewhat above the surface, becoming, by degrees, so thick that it obscures the light of day. When this vapour has ascended high enough in the air to form great clouds, the south wind rises, and the rain again pours down upon the earth. Then the sky becomes clear once more, and once more the vapour rises and rises, and so it goes on. These atmospheric revolutions continue for a fortnight. Meanwhile, the earth is in a sort of fermentation: all the animals keep crouching on the ground, and men, women, and children feel, in every limb, vague, indescribable discomfort and disability. The Si-Fan call this period the season of land vapours.