^0 Hints for a Theory of the Earth. 



pholades ; to fearch alfo for veftiges of the labours of man, 

 fuch as excavations, rings for making faft veflels ; in a word, 

 to endeavour to afcertain whether the fea has the fame level 

 as it had in the remoteft ages. 



3. In cafe the level has changed, to examine whether that 

 efTecl has been produced by a change in the fea itfelf, or 

 whether the more rather has not been raifed or deprefled. 



4. If the fea coaft is flat, to difcover to what diftance its 

 acclivity is infenfihle ; and to examine the nature of the fand 

 found on the fhore. 



5. Whether the grains of that fand are round or angular, 

 cryftallifed or not, quartzy or calcareous, or of any other 

 kind of flone. 



6. To endeavour to difcover its origin, whether it can be 

 confldered as produced by detrition from the neighbouring 

 mountains or hills; whether it may not have proceeded from 

 fome river which had its mouth in the neighbourhood, or 

 whether it may not have been brought from the bottom of 

 the fea itfelf by the tide and the waves ? 



7. Whether this fand contains, like that of Rimini, mi- 

 crofcopic fliclls of the order of thofe called pelagian P 



8. Whether there are not fliclls on the borders of the 

 fea; and, if there are, to determine thofe by which that 

 coaft feems to be chara&erifed. 



9. Whether there are any rolled pebbles ? 



10. To examine, as in No. g, chiefly on the fhore, and 

 even pretty far up the country, whether there are any proofs 

 that the fea gains on the land, or the latter on the fea ; and, 

 in cafe the fea feems to recede, to difcover whether that may 

 not be occafioped by the land rifing by accumulations warned 

 down from the higher grounds ; by fubterranean caufes, or 

 reciprocally. 



11. If a progreffive difplacing of the ocean really exifts, 

 by what obfervations can the fyftems, which tend to explain 

 jt, be verified ? Some have employed, for that purpofe, the 

 currents produced by the trade winds 3 others, the fhock of 



the 



