FOSSIL-SHELLS, ETC. 349 



into peculiar shapes, so these seeming snails, cockles, and 

 mussel -shells, are only sportive forms that nature assumes 

 amongst others of its mineral varieties : they have the 

 shape of fish, indeed, but they have always been terrestrial 

 substances." 



With this plausible solution mankind were for a long 

 time content ; but upon closer inquiry, they were obliged 

 to alter their opinion. It was found that these shells had 

 in every respect the properties of animal, and not of 

 mineral nature. They were found exactly of the same 

 weight with their fellow shells upon shore. They answered 

 all the chemical trials in the same manner as sea-shells do. 

 Their parts, when dissolved, had the same appearance to 

 view, the same smell and taste. They had the same 

 effects in medicine, when inwardly administered ; and, in 

 a word, were so exactly conformable to marine bodies, that 

 they had all the accidental concretions growing to them, 

 (such as pearls, corals, and smaller shells,) which are found 

 in shells just gathered on the shore. They were, therefore, 

 from these considerations, given back to the sea ; but the 

 wonder was, how to account for their coming so far from 

 their own natural element upon land. 



As this naturally gave rise to many conjectures, it is not 

 to be wondered that some among them have been very ex- 

 traordinary. An Italian, quoted by Mr. Buffon, supposes 

 them to have been deposited in the earth at the time of the 

 crusades, by the pilgrims who returned from Jerusalem ; 

 who gathering them upon the sea-shore, in their return car- 

 ried them to their different places of habitation. But this 

 conjecturer seems to have but a very inadequate idea of 

 their numbers. At Touraine, in France, more than a hun- 

 dred miles from the sea, there is a plain of about nine 

 leagues long, and as many broad, whence the peasants of 

 the country supply themselves with marl for manuring 

 their lands. They seldom dig deeper than twenty feet ; 



