In this history we have the process of building a log-house, and the usual modes of assembling round the squatter such of the comforts of life as may be obtained in the desert; but our family Robinson appears to have been the most ingenious as well as the most fortunate of adventurers, for there are very few, even of the luxuries of civilised society, which are beyond his reach. The natural history of the book, however, is its main feature; and the adventures of the lost family with the unreasoning denizens of the desert remind us not unfrequently of the pictures of Audubon. This is among the earliest:--'There were high cliffs fronting us, and along the face of these five large reddish objects were moving, so fast that I at first thought they were birds upon the wing. After watching them a moment, however, I saw that they were quadrupeds; but so nimbly did they go, leaping from ledge to ledge, that it was impossible to see their limbs. They appeared to be animals of the deer species, somewhat larger than sheep or goats; but we could see that, in place of antlers, each of them had a pair of huge curving horns. As they leaped downward, from one platform of the cliffs to another, we fancied that they whirled about in the air, as though they were "turning somersaults," and seemed at times to come down heads foremost! There was a spur of the cliff that sloped down to within less than a hundred yards of the place where we sat. It ended in an abrupt precipice, of some sixty or seventy feet in height above the plain. The animals, on reaching the level of this spur, ran along it until they had arrived at its end. Seeing the precipice, they suddenly stopped, as if to reconnoitre it; and we had now a full view of them, as they stood outlined against the sky, with their graceful limbs and great curved horns, almost as large as their bodies. We thought, of course, they could get no farther for the precipice, and I was calculating whether my rifle, which I had laid hold of, would reach them at that distance. All at once, to our astonishment, the foremost sprang out from the cliff, and whirling through the air, lit upon his head on the hard plain below! We could see that he came down upon his horns, and rebounding up again to the height of several feet, he turned a second somersault, and then dropped upon his legs, and stood still! Nothing daunted, the rest followed, one after the other, in quick succession, like so many street-tumblers; and, like them, after the feat had been performed, the animals stood for a moment, as if waiting for applause!' These were the _argali_, or wild sheep, popularly termed bighorns, and resembling an immense yellow goat or deer furnished with a pair of ram's horns.