The following is the account given of the mountain called Pichincha, by Don George Juan, and Don Antonio de Ulloa, two mathematicians, sent by the kings of France and Spain, to make observations in relation to the figure of the earth. These mathematicians suffered extremely, as well from the severity of the cold, as from the impetuosity of the winds, which on these heights blow with incessant violence; difficulties the more painful, as they had been little used to such sensations Thus, in the torrid zone, nearly under the equi noctral line, where it is natural to suppose they had most to fear from the heat, their greatest pain was caused by the ex-cessiveness of the cold. Their first scheme, for shelter and lodging in these uncomfortable regions, was to pitch a field-tent for each company : but on Pichinca, this could not be done, from the narrowness of the summit; they were therefore obliged to be contented with a hut so small, that the whole of the company could scarcely creep into it. Nor will this appear strange, if the reader considers the bad situation and smallness of the place, it being one of the loftiest crags of a rocky mountain, 100 fathoms above the highest desert of Pichinca. Such was the position of their mansion, when all the other adjacent parts soon became covered with ice and snow. The ascent up this stupendous rock, from the base, or the place where the mules could come to their habitation, was so craggy, as only to be climbed on foot; and to perform it, cost them four hours' continual labour and pain, arising not only from the violent efforts of the body, but the subtilty of the ail, which was so thin, and probably overcharged with the lighter respirable gases, as to render respiration difficult.

Our philosophers generally kept within their hut. Indeed, they were obliged to do this, on account of the intenseness of the coid, the violence of the wind, and their being continually involved in so thick a fog, that an object at six or eight paces was hardly discernible. When the mist cleared up, the clouds, by their gravity, moved nearer to the surface of the earth, and on all sides surrounded the mountains to a vast distance, forming no bad representation of the sea, with their rock, like an island, stationed in its centre. When this happened, they heard the horrid noises of the tempests, which then spent their fury on Quito and the neighbouring country. They saw the lightnings issue from the clouds, and heard the thunders roll far beneath them; and whilst the lower parts were involved in tempests of thunder and rain, they enjoyed a delightful serenity, the wind was hushed, the sky became clear, and the enlivening rays of the sun moderated the severity of the cold. But their circumstances were very different, when the clouds reascended: their thickness rendered respiration difficult; the snow and hail fell continually; and the wind returned with all its violence; so that it was impossible entirely to overcome the fears of being, together with their hut, blown down the precipice, on the edge of which it was built, or of being buried by the daily accumulations of ice and snow.

The wind was often so violent in these regions, that its velocity dazzled the sight, whilst their fears were increased, from the dreadful concussions of the precipice, caused by the fall of enormous fragments of rocks. These crashes were the more alarming, as no other noises are heard in such solitary abodes : and during the night, their rest, which they so greatly wanted, was frequently disturbed by these sudden sounds. When the weather was fair near their hut, and the clouds gathered about some of the other mountains which they had selected for their observations, so that they could not make all the use they desired of this interval of good weather, they left their hut, to exercise themselves. Sometimes they descended to a small distance; and, at other times, amused themselves with rolling large fragments of rocks down the precipice; and these frequently required the joint strength of them all, though they often saw the same effected by the mere force of the wind. But they always took care, in their excursions, not to go so far out, but that, on the least appearance of the clouds gathering about their cottage, which often happened very suddenly, they could regain their shelter. The door of their hut was fastened with thongs of leather, and on the inside not the smallest crevice was left unstopped ; besides which, it was very compactly covered with straw : but, notwithstanding all their care, the wind penetrated through.

The days were often little better than the nights; and all the light they enjoyed, was that of a lamp or two, which they kept continually burning. Though their hut was small, and crowded with inhabitants, besides the heat of the lamps, yet the intenseness of the cold was such, that every one of them was obliged to have a chafing-dish of coals. These precautions would have rendered the rigour of the climate support-able, had not the imminent danger of perishing, by being blown down the precipice, roused them every time it snowed, to encounter the severity of the outward air, and sally out, with shovels, to force from the roof of their hut, the masses of snow which were gathering on it. Nor would it, without this precaution, have been able to support the weight. They were not indeed without servants and Indians, but these were so benumbed with the cold, that it was with great difficulty they could get them out of a small tent, where they kept a continual fire. So that, all our artists could obtain from them, was to take their turns in this labour; and even then they went very unwillingly about it, and consequently performed it but slowly.

The reader may easily judge what our philosophers suffered from the asperities of such a climate. Their feet were swelled, and so tender, that they could not even bear the heat of the fire, and walking was attended with extreme pain. Their hands were covered with chilblains; their lips swelled and chopped, so that every motion in speaking drew blood; consequently they were obliged to observe strict taciturnity, and were little disposed to laugh, as, by causing an extension of the lips, it produced such wounds as were very painful for two or three days after.

Their common food in this inhospitable region was a little rice boiled with some flesh or fowl, procured from Quito; and, instead of fluid water, their pot was filled with ice: they had the same resource with regard to what they drank; and while they were eating, every one was obliged to keep his plate over a chafing-dish of coals, to prevent his provisions from freezing. The same was done respecting the water. At first they imagined the drinking of strong liquors would diffuse a heat through the body, and consequently render it less sensible of the painful sharpness of the cold; but, to their surprise, they felt no manner of strength in such liquors, nor were they any greater preservatives against the cold than even common water.

It is affirmed, that there are in the Andes sixteen volcanoes, or burning mountains, which throw out fire and smoke with a terrible noise. The height of Chimborazo, said to be the highest peak of the Andes, has been determined by geometrical calculations to be 20,282 feet. As all or most rivers have their source in mountains, it is no wonder a great num-ber run down the sides of the Andes. Some hurry along with a prodigious rapidity, while others form beautiful cascades, or run through holes in rocks, which look like bridges of a stupendous height. There is a public road through the mountains, 1000 miles in length, part of which runs from Quito to Cusco.