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in Ireland, protected by the uncultivated wilds and the misrule of the country until the year 1710.

In this outline of the pre-historic animals associated wih man, I have attempted to prove that the animals of the neolitic and bronze ages in Britain are identical with those found in peat-bogs and alluvia, and that the whole group so constitcted differs totally from the post-glacial group of animals. And I have striven to show their relation to the animals now living in Britain. Their comparison with the pre-historic fauna of the Swiss lakes, or that of Scandinavia, Germany, France, ani Italy, I must leave to the savants of those countries. The modification of that fauna I have shown to be the result of man's influence, and I cannot help believing that the disappearance of the larger animals associated with man in post-glacial times, is in a measure owing to the same cause, as well as to climatal or geographical change. With the larger carnivores man must have waged a war of extermination; while the larger ruminants on which he fed must have found the difficulty of concealment increase in proportion to their size. There is a great gulf fixed, so to speak, representing an inconceivable length of time between the post-glacial and pre-historic periods; and the fauna of Europe, as we have it now, dates from the latter epoch. In Britain, of course, insulated from the mainland of Europe, several animals probably introduced into Europe after that insulation, have not been found, such as the chamois and bouquetin. Had Britain been united to France during the rein-deer epoch, we might have expected to find the remains of those animals.

ELECTRICAL COUNTRIES.

BY M. J. FOURNET.*

(Continued from our September Number.)

In a preceding article upon electrical countries, I especially directed my investigations to remote regions. It now remains, therefore, to concentrate the field of these researches, and to remark that in the mountains of the basin of the Rhone, and those in connection with them, there are some places which are distinguished by electrical discharges of a very remarkable intensity, whilst up to the present time the most absolute silence reigns in others, notwithstanding the apparent identity of surfaces. I hope that the details which follow may excite some attention in observers so that at last some meteorological law may be established. Leaving, therefore, for the present, the details already mentioned by M. Arago, I shall first consider that which concerns the Alpine and Jurassic group, and afterwards return to the most western parts of our country.

ALPINE ELECTRICITY.
1. Illumination of the rocks of Mont Blanc.

A. During the night of the 11th of August, 1854, Mr. Blackwell being stationed on the Grands Mulets (altitude 3455 mètres), the guide, F. Le Couttet, went out of the cabin about 11 o'clock at night, and saw the crests of these mountains all on fire. He made this circumstance immediately known to his companions, they all wished to be assured as to the fact, and they saw that by an effect of electricity produced by the tempest, each one of the adjacent rocky projections appeared illuminated. Their clothes were literally covered with sparks, and when they raised their arms their fingers became phosphorescent.

At the same hour we had at Lyons rather a violent shower with thunder, from the south-west, and the whole of the day had been very stormy.

According to information, for which I am indebted to M. V. Payot, a naturalist universally known, the guide, Couttet, of Chamounix, at the time of his ascent of Mont Blanc the 25th of August, 18+1, with M. Chénal, was surprised by a storm on the Grands Mulets which placed them in actual danger on account of the thunder and lightning which surrounded them without intermission. All the stones around them had

* Translated from the “Comptes Rendus."

their electrical sparks, and yet the summit of Mont Blanc as well as the sky were perfectly serene.

2. Electricity on the Breven.-In 1767, during rery stormy weather, De Saussure, Jalabert, and Pictet were on the Breven (altitude 2500 mètres). There they had only to raise a hand and to extend a finger to feel a kind of pricking at the extremity. This remark, first made by Pictet, was soon followed by another, that as the sensation became more apparent it was accompanied with a kind of whistling. Jalabert, whose hat was trimmed with gold lace, heard a fearful buzzing round his head. They drew the sparks from the button of his hat as well as from the ferrule of his cane. At last the storm was so violent in the cloud which was in the same plane with their heads, that they were obliged to descend from the summit to 20 or 24 mètres lower, where they no longer felt the electrical influences.

3. Electricity of the snow lying on the soil of the Jungfrau. -Snow lying on the ground, does not prevent these mani. festations; this fact results from the following details. On the 10th of July, 1863, Mr. Watson, accompanied by several other tourists and guides visited the summit of the Jungfrau. The morning was very fine, but on approaching the sunmit they perceived large clouds piled upon it, and when they had almost reached it, they were assailed by a tremendous puff of wind accompanied with hail. After some minutes they were obliged to make a retreat, and during their descent the snow continued to fall in such a quantity that the little troop, mistaking the direction, travelled for some time in the Latoch-Sittel. They had scarcely perceived their error when they heard a violent clap of thunder, and soon afterwards Mr. Watson heard a kind of whistling which proceeded from his stick. This noise resembled that which a kettle makes when the water boils briskly. They halted and remarked that their sticks, as well as the hatchets with which each was provided, produced a similar sound. These objects did not discontinue their singular whistling even when one end was placed in the snow. Presently one of the guides took off his hat, exclaiming that his head was burning. His hair literally stood on end like that of a person who had been electrified under the influence of a very powerful machine, and all experienced a sensation of pricking and heat in their faces and other parts of the body: Mr. Watson's hair was straight and stiff, a veil which was round another traveller's hat was lifted vertically, and they heard the electrical whistling at the end of their fingers when moved in the air. Even the snow emitted a sound analagous to that which is produced by a sharp hail-storm. There was not, however, any appearance of light, which must have been the case had it been night. Other claps of thunder suddenly stopped these phenomena, which recommenced, however, before even the grumbling of the clap had been echoed through the mountains. They all experienced an electrical shock, more or less violent, in several parts; Mr. Watson's right arm was paralysed for several minutes till one of the guides pinched it violently with his hand; but he felt a pain in his shoulder for several hours. At last, about half-past twelve o'clock, the clouds dispersed and these effects disappeared, after having been felt for about twenty-five minutes. At Lyons a brisk north wind completely neutralized these stormy manifestations.

4. Electricity of the Piz Surley.--A little more to the east are the Grisons which touch Italy, concerning which M. H. de Saussure, whose observations made in Mexico I have already mentioned, has just forwarded to me the following note :

« The 22nd of June 1865, setting out from Saint Moritz (Grisons) I ascended the Piz Surley, a granitic mountain whose summit, more or less conical, rises to the height of 2300 mètres. During the preceding days the north wind had persistently prevailed; it became variable on the 22nd, and the sky was covered with wandering clouds. Towards noon, these vapours increased, reuniting above the highest, and in other directions keeping high enough not to hide the greater part of the summits of the Engadine, upon which local showers soon fell.

Their appearance of dusty vapours half transparent caused us to think that it was only a shower of hail and snow or sleet.

“ About one o'clock at night we were overtaken by a fine sleet, thinly scattered, while similar showers of hail enveloped the greater number of the rocky peaks, such as the Pic Ot, Pic Julier, Pic Languard, and the snowy summits of the Bernina : whilst a violent shower of rain fell in the valley of Saint Moritz.

« The cold increased, and at half past one o'clock p.M., having arrived at the summit of the Piz Surley, the fall of sleet becoming heavier, we prepared to take our repast, near a pyramid of dry stones, which crown the summit. Whilst resting my cane against this construction, I experienced a violent pain in my back, at the left shoulder, which resembled that which would be produced by slowly thrusting a pin into the flesh, and in taking away my hand without finding anything, I felt a similar prick in my right shoulder. Then supposing that my linen overcoat contained some pins, I threw it of; but instead of finding any alleviation, my pains increased, stretching across my back from one shoulder to the other, accompanied by a sensation of tickling, and painful stinging, like that which might be produced by a wasp or some other insect in my clothes riddling me with pricks.

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Taking off a second coat I did not discover anything which could have wounded me, while the pain assumed the character of a burn. Without reflecting, I fancied my woollen shirt had taken fire and was going to undress myself ccm. pletely when our attention was drawn to a noise which reminded us of the humming of wasps. It was produced by our sticks which sang loudly and resembled the noise of a kettle when the water is on the point of boiling ; this lasted, perhaps, about twenty minutes. . . . Some moments after, I feit my hair and my beard stand on end, which produced upon me 9 similar sensation to that which results from a dry razor being passed over stiff hair. A young man, who accompanied me, exclaimed that he felt all the hairs of his moustache growing, and that from the top of his ears there were strong currents. ... A clap of distant thunder towards the west warned as that it was time to quit the summit, and we descended rapidly for about a hundred mètres. Our sticks vibrated less and less as we descended, and we stopped when the sound had become sufficiently weak, only to be heard by putting our ears close to them. The pain in my back had ceased with the few first steps of descent, but I still retained a slight sensation of it. A second clap of thunder, ten minutes after the first was heard in the west over a considerable distance, and this was the last. There was not any lightning, and half an hour after we left the summit the sleet had ceased and the clouds dispersed. At halfpast 2 o'clock P.M. we again reached the culminating point of the Piz de Surley to look for the sun. The same day there was a violent storm in the Bernese Alps, where an English lads was struck by lightning

“After all, we considered that these phenomena must have extended to all the high rocky points of the Grisons, eren to the horizon where there were several stony summits, like that on which we were, enveloped by whirlwinds of sleet, while the high snowy points of the Bernina seemed to have been exempt, notwithstanding the scattered clouds which surrounded them. . . . . On a previous occasion at Nevado de Toluca I had been present at scenes of the same kind, but much more severe, on account of its tropical situation and its height of 4548 mètres.

“However, in bringing together different observations, many points in common can be distinguished amongst them, viz., 1st. The flow of electricity from the culminating rocks is produced under a stormy sky covered with low clouds, enveloping the summits or passing at a very little distance above them, but without there being any electrical discharges in the neighbourhood of the place where the continual flow is manifested.

“ 2nd. In each of the cases observed the summit of the

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