THE second ascent of Ben Nevis for the winter was made on Saturday last by Mr. Livingstone, Fort William, to read the thermometer at the station of the Scottish Meteorological Society on the top of the mountain. The depth of snow was found to be much greater at the top than on the occasion of the previous visit. On the edge of the precipices the snow lay to a depth of fifteen to twenty feet, the Ordnance Survey Cairn barely overtopping it, and the hut built for the accommodation of Mr. Wragge during summer being almost completely buried under the snow-wreaths. The depth of the snow rapidly diminished in the direction of the protecting-cage for the thermometers, outside which it was only three feet deep. Inside the cage, fortunately, there was scarcely any snow, thus leaving the registering thermometers free. The maximum thermometer read 32°.1, and the minimum 13°.2, these being the extremes of temperature at the top since the date of the previous visit on December 3 (NATURE, vol. xxv. p. 135), The temperature at the time of the visit, 1 p.m., was 31°.4 in the cage, and by thermomètre froid, 33°.1. The spring near, the summit was deeply buried in snow, but the spring at 2500 feet high was open, and the temperature of its water was 37°.3, the air at the same place being 41°.0. The temperature of the water of the Lake was 42°.1, and that of the air at the same height 44°.8. At Fort William the maximum temperature for the same day was 53°.5, and the minimum in December 23°.5, and in January 26°.8. Hence the temperature at the top had fallen only about 10°.0 lower than the lowest at the level of the sea during the winter. The day was very favourable for the ascent, which was made without difficulty. Though it had rained heavily at Fort William on the Friday, no fresh snow had fallen on the Ben, and as the afternoon sun softened the snow some-what, the descent was very easy, the first 2000 feet being done in thirty-three minutes. The observations made on these two occasions show that as the snow accumulates to such great depths near the edge of the precipice, the observatory it is proposed to erect should be built at some distance from it.