OBSERVAT ION S

ON THE

FORMATION OIF MOUNTAIN'S IN GiENEBAIL;

AND MORE PARTICULARLY OF

THOSE WHICH SCREEN THE LAKE OF GENEVA ;WITH THEIR CONSEQUENCES,

IN ORDER TO EXPLAIN AND ELUCIDATE THE ORIGIN OF THE LAKE ITSELF.

Impressed with a conviction of the extreme difficulty which must attend the deduction ofany thing in the form of a system, from inspecting or examining those effects or consequenceswhich now present themselves to our view in the great and stupendous features of Nature, and ofascertaining the various revolutions which the earth has undergone, from its first great shock, or< convulsion, through sundry subsequent periods to the present, I venture, with extreme diffidence,to hazard my sentiments or conjectures on the causes which appear to me most likely to haveoperated in producing, in most of the mountains and hills which constitute the Alps (thoughmore particularly those which environ the Lake of Geneva ), that difference in their direction andstructure, as well as abruptness in their strata, which is at present so conspicuous. It is with noless diffidence that I shall annex some notice relative to the formation of the beds of sand-stone,in many places intermixed with others of pebbles, sand, and sometimes with a species of calcareouspudding-stone, gypsum, lithanthrax, or fossil-coal, &c. and, in fine, my ideas on the origin of thelake, the valleys which terminate contiguous to it, and the great revolutions doubtless experiencedin that part of the Alps prior to the formation of this extensive and noble basin. Yet before Idare propose my conjectures on such difficult and important subjects to geology, it may benecessary to observe, that the present work, as well as my former publications, being simple narra-tives, or local descriptions, to which I have subjoined reflexions or observations spontaneouslyoccasioned by the curious state of the places which I visited, I have avoided, as much as possible,long and tedious details on geology and lithology, reserving to some future day the design ofgiving a more ample explanation of those sciences, as a supplement to my Tableau des Alpes, awork begun about twenty years ago. I shall here likewise inform my reader, that, knowing theextreme, and I may add the almost insurmountable difficulties, experienced by those who hithertohave endeavoured to give a general theory of the earth, I am far from wishing to he understood asattempting such an undertaking,—being thorougly convinced, as mentioned in a former work, thatit must be deemed impossible to proceed with certainty in this laborious and wide pursuit, and toexplain the solution of that great problem, until a sufficient number of facts and observations becollected on the subject, in order to draw some certain consequences from thepi, to serve, as itwere, for a basis; and which, not being repugnant to our judgment, shall agree with the curiousand wonderful natural phenomena with which our globe abounds. Nevertheless, as it is impos-sible to make any considerable progress either in geology or lithology, without having previouslyformed some notions on the origin and formation of mountains, I shall here subjoin some fewideas relative to those subjects.

As to the origin of the primitive mountains, naturalists are at present mostly agreed that theirformation may be attributed to an aggregate crystallisation of vitrifiable parts, such as quartz,feldspath or felspar, mica, schorl, &c. originally crystallised in the menstruum, or ambient fluid,which at that time covered the globe to such an extreme height, as to surpass the tops of themost elevated peaks of the Andes or Cordeleras, in South America , as well as the primitive chainof the Alps , Sc c.

Q