83 “There is, therefore, little hope of thus arriving at anything decisive as to the exact part which echoes take in the production of the rolling sound of thunder.” P. 165, English ed., translated by Col. Sabine: Longmans, 1855. 84 The same has seemed to me to be the case at all times when I have been close to the points of explosion. There has been always a distinct interval between the first explosion and the rolling sounds and secondary explosions which I have _believed_ to be merely echoes; but it has never been possible (except in the above-mentioned case) to _identify_ them as such. Others have observed the same. “The geologist, Professor Theobald, of Chur, who was in the Solferino storm, between the Tschiertscher and Urden Alp, in the electric clouds, says that the peals were short, like cannon shots, but of a clearer, more cracking tone, and that the rolling of the thunder was only heard farther on.” Berlepsch’s _Alps_, English ed., p. 133. 85 Mr. J. Glaisher has frequently pointed out that all sounds in balloons at some distance from the earth are notable for their brevity. “It is one sound only; _there is no reverberation, no reflection_; and this is characteristic of all sounds in the balloon, one clear sound, continuing during its own vibrations, then gone in a moment.”—_Good Words_, 1863, p. 224. I learn from Mr. Glaisher that the thunder-claps which have been heard by him during his “travels in the air” have been no exception to the general rule, and the absence of rolling has fortified his belief that the rolling sounds which accompany thunder are echoes, and echoes _only_. 86 See Appendix B for the experiences of Mr. R. B. Heathcote during a thunderstorm on the Matterhorn in 1869. 87 Since then (on at least one occasion), several persons have found themselves in this predicament for five or six consecutive days! 88 I am speaking exclusively of the disturbances which occur in the day-time during fine weather. 89 The rocks are sometimes so hot that they are almost painful to touch. 90 The mists are extremely deceptive to those who are on the mountain itself. Sometimes they _seem_ to be created at a _considerable distance_, as if the whole of the atmosphere of the neighbourhood was undergoing a change, when in reality they are being formed in immediate proximity to the mountain. 91 Croz was born at the Village du Tour, in the valley of Chamounix, on April 22, 1830; Almer was a year or two older. 92 The Pointe des Ecrins is also seen from the top of the Col de Valloires, rising above the Col du Galibier. This is the lowest elevation from which I have seen the actual summit of the Ecrins.