OF THE FRENCH GEOLOGICAL SOCIETY. 413 
really elegant outline which the range of the Vosges presented, and 
learnt for the first time that the valleys within the chain, and the 
general character of the country and its inhabitants, are as interest- 
ing, and even picturesque, as the scenery which attracts so many 
travellers to many parts of Switzerland and Germany. But this by 
the way, and as a hint to future travellers in the east of France. 
Having stopped a little on this rising ground to collect our forces, 
which had been rather scattered, in consequence of a little foraging 
which had gone on in a village through which we had passed, we 
continued to ascend till we reached the principal summit of the 
Portland oolite, beyond which there is a very slight descent, and a 
narrow and inconsiderable valley, enclosed on the other side by the 
lower beds of the oolite, here lifted up, and forming the highest part 
of the ridge ; while in the valley itself there occurs a bed of clay, 
probably identifiable with our Kimmeridge clay. To explain this 
appearance more clearly—and it is one of the effects of disturbance 
most frequent in this part of the Jura—let the reader imagine a 
succession of strata, of which the three uppermost are stone, clay, 
and stone, lifted up into a ridge by a force from below. It is not 
difficult to conceive that in binding thus a brittle stone, the upper 
bed, not defended by pressure from above, will break, and be exposed 
to very rapid degradation by atmospheric causes, when the effort 
which raised the mountain has ceased to act. Thus, after some time 
the broken capping of stone will be destroyed; the clay, which 
came next, being soft, is early washed away ; and nothing remains 
but the part originally lowest, now forming a central ridge higher 
than the other beds. But, again, the capping of upper oolite we 
spoke of as broken, would only be much injured within a moderate 
distance of the line of extreme pressure, and therefore along the 
sides of the hill it would be more solid, and less liable to injury. 
Just so we find it: we have an irregular ridge, not so high as the 
central ; then a valley, caused simply by the more rapid washing 
away of the clay than the stone beds ; and lastly, in the centre, the 
stratum lowest in formation highest in accidental locality. This 
description of one very numerous class of disturbances in all hilly 
countries, especially the west of Switzerland and the east of France, 
may be useful to those not much accustomed to geological generali- 
zations ; and it need only be added that we have here described a 
simple case of “ anticlinal axis,” a word in common use, but of 
which a direct explanation is hardly to be given without mathema- 
tics, although this indirect way, by example, may perhaps be clear. 
It will be apparent, from all that has been said, that the inelina- 
