The best period for making the ascent is between May and September, after the melting of the winter snows, and before the autumnal rains. In winter snow frequently extends from the summit downwards for nine or ten miles; the paths are obliterated, and the guides refuse to accompany travellers. Even so late in the spring as May 29th Brydone had to traverse seven miles of snow before reaching the summit. Moreover, violent storms often rage in the upper regions of the mountain, and the wind acquires a force which it is difficult to withstand, and is at the same time piercingly cold. Sir William Hamilton, in relating his ascent on the night of June 26th, 1769, remarks that, if they had not kindled a fire at the halting place, and put on much warm clothing, they would "surely have perished with the cold." At the same time the wind was so violent that they had several times to throw themselves on their faces to avoid being overthrown. Yet the guides said that the wind was not unusually violent. Some writers, well used to Alpine climbing, have asserted that the cold on Etna was more severe than anything they have ever experienced in the Alps. The writer of this memoir made the ascent of the mountain in August 1877, accompanied by a courier and a guide. We took with us two mules; some thick rugs; provisions consisting of bread, meat, wine, coffee, and brandy; wooden staves for making the ascent of the cone; a geological hammer; a bag for specimens; and a few other requisites. It has to be remembered that absolutely nothing is to be met with at the Casa Inglesi, where the halt is made for the night; even firewood has to be taken, a fire being most necessary in those elevated regions even during a midsummer's night. For some time previous to our ascent the weather had been uniformly bright and fine, and there had been no rain for more than three months. The mean temperature in the shade at Catania, and generally along the eastern sea-base of the mountain, was 82° F.