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and which, from the circumstance of its scarcely ever raining on the high Alps during the winterseason, decreases as considerably in January, February, and March.

Besides this periodical fluctuation, its waters experience a kind of flux and reflux, called seichesby the people of the country. This phenomenon, which generally occurs during tempestuousweather, has been known to take place even in a calm; but the circumstance is singular. The■waters, at those times, are seen to .rise rapidly to the height of about five feet, and to fall as sud-denly, and thus successively for several hours; while a rumbling noise is heard, not unlike the ex-plosion or firing of distant guns. Many have been the conjectures and suppositions of the Gene-vese naturalists to account for this phenomenon, which is no-where so conspicuous as near the ex-tremities of the lake. By some of those eminent men it has been ascribed to the effects of asudden shock of the wind; by others to th e. refoulement, or ebbing of the river Arve ; while,again, others have attributed it to the action of electrical clouds, which, when, passing over thelake,, have by attraction raised the waters to the height above mentioned, and so produced thatkind of undulation. Now, as I do not exactly acquiesce in those ideas, I shall here beg leave tostate my own suppositions, having had frequent opportunities of witnessing the effects of thoseseiches, and, like others, been tempted to search into their cause.

From what I have observed, I have been induced strongly to suspect that this singular effectmay in some degree be ascribed to the currents which exist at the bottom of the lake, inde-pendent of those of the rivers which throw themselves into it; as likewise to the subterraneousair, called vandaise by the Genevese watermen,—which, by rising to the surface of the lake,so frequently occasions storms; besides many ptber causes, which I may in future endeavour toexplain.

Water spouts have also been observed to have risen on the lake to one hundred and thirtytoises above the surface of the water, in the shape of a funnel, extending thirty-five toises in dia-meter, though happening at all times invariably where the depth of water is' the greatest, or be-tween Meillerie , Lausanne , and Vevay.

These phenomena do not often happen; but, when they do, ought assuredly to be reckonedas curious as those which are now and then observable on the ocean.

The lake, in the environs of Geneva, as before mentioned, decreases both in width and depth;and a quarter of a league from the harbour, or Cape Secheron, to the hills of Cologny , is crossedby a bank of argillaceous earth of tolerable thickness, at all times covered by the water, thoughfrom seven to eight feet higher, and in some places more, than the common or original bed of thelake. The abrupt state of its declivity, and the chamfreted appearance of its border or edge, giveit the exact resemblance of a fissure experienced in that particular part; whereas, contiguous toGeneva, it is evident that the bed of the lake has retained its original height, a supposition noways improbable.

On this,bank, called Le Travers, which is in great part covered with sand and pebbles, stands?near the Pagnis, a huge granitic stone, universally known to the Genevese by the appellation ofPierre-a-Nitton, being a corruption of the word Neptune ;—it being a received opinion amongthem that on this stone originally stood an altar dedicated to that god.

This block of granite, as well as many others of similar kind, found on the hills which screenthe basis of the Jura , the Vouaches, and the Saldve, to an elevation of five hundred feet at least,merit attention, and must be deemed curious, being visibly foreign to the places where they nowstand, and cannot possibly have come from any part, except the highest primordial peaks of theAlps . Similar pieces have I likewise remarked, as well as lameliated hornstone and primitive rock,in several places on the banks of the lake, and on the road from Geneva to Evian. Now, as tothe manner in which they may have been conveyed to those places, the force which has acted onthem, or rather by what convulsion or operation of Nature they may have been thrown there, arequestions difficult to resolve; yet I shall hereafter venture to hazard my opinion on this subject.

But to return to Geneva.—Considering this city as seated at the extremity of this noble lake,and on the declivity of two hills, separated only by the course of the Rhone, which, on breakingout of the lake, flows through the city nearly from east to west, in a smooth, deep, and transparentstream, it may be said not only to command one of the most pleasing and well-cultivated countriesit is possible to conceive, but in fact to become, from whatever point it is viewed, an interestingobject. (Vide N° XIII.)

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