448 ON THE GEOLOGY OF THE 



At the Castle Rock of Nice, the bones occur in two distinct 

 states ; one forming a very hard indurated brescia, the paste of 

 which varies from a brown to a colour almost black ; in the 

 other they are loose, or feebly agglutinated, by means of calca- 

 reous infiltration, with fragments of limestone and sea-shells, 

 showing that the sea still continued its operations when the re- 

 volution which occasioned this deposite took place. 



That the sea had retired and again risen, or that a wave had 

 flowed over this quarter, and in retiring had drawn these de- 

 bris along with it, is most probable, as there appear to be se- 

 veral fissures very different from those formerly mentioned. 

 Some containing a few dispersed fragments of bones, and 

 others nothing but loose earth and stones, and which pro- 

 bably had been produced by some convulsion long after the 

 formation of the Mediterranean marble ; but at a period previ- 

 ous to, or perhaps contemporaneous with, the revolution 

 which brought together the remains of so many different ani- 

 mals. 



On referring to Colonel Imrie's paper, in the 4th volume of 

 the Transactions of this Society, it appears that the bone bres- 

 cias of Nice are in their construction quite analogous to those 

 of Gibraltar, excepting that they are accompanied with traces 

 of marine animals j — while nothing but terrestrial testacea are 

 noticed as accompanying the other. This forms a striking 

 distinction between them ; but it is one which tends rather to 

 involve than to elucidate the history of their formation. 



Some individuals have been anxious to bring down the ope- 

 rations of nature in the formation of the rocks in this vicinity, 

 even to a period subsequent to the civilization of mankind ; and 

 Saussure mentions a story related to him by the French Con- 

 sul in 1787, respecting a copper nail which was said to have 

 been found in the heart of a solid mass of limestone. Some- 

 thing 



