GEOLOGICAL OBSERVATIONS IN FRANCE. Q\;^ 



$6s. [13cl,] the bushel, \ypighing about 130 lbs; and the 



worst fetches 15s. [Zftl.l. The water of a well 18 feet deep, Water at the 



. . r c. r-y > i r. r '^ f • bottom free7.es 



at the bottom of St. George s shaft, freezes on its surface in j„ wmcr. 



winter. On the 27th of. September Deluc's thernpomeler Cokl greater 



stood there at 12'8 fSO'S F.l, while in the open air it was tliani" the 



V -* ' open air. 



at 17-6 [7V6 F.]. The water of this well is extremely 



acid. 



'J'he Vire, which falls into the sea not far from Isigny, forms Sand bank. 

 a considerable bank of sand at its mouth. There is no ap- 

 pearance of cliff here; but at Vierville, a small town on its 

 left bank, and not far from the sea, there are some traces, 

 which soon give way to the sands and downs, that extend to 



Ravenoville 7^ miles N. N. VV. Throughout this space an Shells and zos- 



r I 11 r 11-1 11 1 tera marina 



immense quantity of shells are found, which are collected ^g^.^! ^s ma- " 



and sold to the farmers for dressing their grass land. The nure. 

 zostera marina, which covers the shore, is collected for the 

 same purpose. Thc^ rudiments of cliff seen at Vierville con- 

 sist of horizontal strata of free stone, alternating with clay ; 

 Voth including many petrifactions, particularly gpyphites and 

 ammites. 



At Ravenoville, which lies opposite the isles of St. Mar- Petrosilex, 

 couf, we enter at once upon the primitive class of stones. A 

 beautiful kind of reddish scaly petrosilex forms the transi- 

 tion from the primitive substratum of the peninsula of Cher- 

 bourg to the shelly calcareous stone of the surrounding coun- 

 try. The houses of the neighbouring villages, as well as the 

 forts on the coast of la Hougue, are built with this petro- 

 silex. 



The islands of St. Marconf are probably of a similar rock, 

 since the corresponding coasts of England are; so that, as Granite proba- 



Mr. Delametherie observes, we can scarcely doubt, that the ^^^ extends 



1 r • I ' t I • 1 ' /. 1 1 1 under the sea 



granite extends far into the sea on both sides ol the channel : acoss the 

 and if it were ever to be laid drx', we should probably find channel, 

 the continuation of the gmnitic chain from one country to the 

 other; or at least they would be separated Vonly By a few 

 plains of secondary formation, as are the granites of Biitanny 

 and what was formerly Limousin. 



Ravenoville is perhaps the most northerly place in France, Salt pans^ 

 where salt is made byimitating to a certain point the pro- 



