, est un rocher
qui repond si precisement a un autre rocher de la meme nature, situe de
l'autre cote de la vallee de Courmayeur, qu'on ne sauroit douter qu'ils
n'aient ete anciennement unis par une montagne intermediaire, detruite
par les ravages du temps."

Now, to see how little the situation of the strata influences the shape
of the valleys, I shall transcribe the two paragraphs immediately
following that which has given occasion to the present discussion.

"Un peu au-dela de Nux, la vallee cesse d'etre large et plane, comme
elle etoit dans le environs de la cite; elle devient etroite et tres
variee; la sterile et sauvage, ici couverte de vergers et de prairies
arrosees par la Doire.

"Sec. 961. Les couches des montagnes a notre gauche, qui depuis la cite
avoient constamment couru a l'est et monte au nord, paroissent changer
a un quart de lieue du village de Chambaise, qui est a une lieue et un
quart de Nux. Elles montent d'abord au sud-est, et peu plus loin droit
au sud, tandis que l'autre cote de la vallee elles paroissent monter a
l'est."

In every mountain, and in every valley, the solid parts below have
contributed in some manner to determine the shape of the surface of the
earth; but in no place is the original shape of the earth, such as it
had first appeared above the sea, to be found. Every part of the land is
wasted; even the tops of the mountains, over which no floods of water
run, are degraded. But this wasting operation, which affects the solid
rock upon the summit of the mountain, operates slowly in some places,
compared with that which may be observed in others. Now, it is in the
valleys that this operation is so perceptible; and it is in the valley
that there is such a quick succession of things as must strike the mind
of any diligent observer; but this is the reason why we must conclude,
that at least all the valleys are the operation of running water in
the course of time. If this is granted, we have but to consider the
mountains as formed by the hollowing out of the valleys, and the valleys
as hollowed out by the attrition of hard materials coming from the
mountains. Here is the explanation of the general appearance of
mountain and valley, of hill and dale, of height and hollow; while each
particular shape must have its dependence, consequently its explanation,
upon some local circumstance.

But, besides the general conformation of mountains and valleys, there
may be also, in the forms of mou