314 ON THE DEPOSITS CALLED TERTIARY 



most, and under a want of relation or parallelism to 

 those strata. Thus they are easy to discover and 

 assign; and it is no credit to geologists that they were 

 so long overlooked,, and so perpetually confounded 

 with the secondary, and even, with the primary strata, 

 as had been done in the case of the " bituminous marl 

 slate." I shall commence by making those distinctions 

 among them which have not yet been made ; and 

 thence, as I hope, elucidate the whole subject. 



I must first reject entirely those strata, be they 

 hard or loose, and whatever remains they may con- 

 tain, marine, or terrestrial, which occur in any place 

 or country, where it can be shown by geographical 

 investigation, that they have formed a portion of the 

 bottom of the actual ocean. The remark, thus 

 stated, seems so simple, that every one will accede to 

 this exclusion : and yet that distinction has been so 

 little made, that many of the tertiary strata described, 

 are of this nature : as these discreditable errors have 

 produced a very great part of the confusion which 

 has encumbered this subject. And let it be remem- 

 bered, that if the bottom of the present ocean extends 

 to the foot of the mountains of Upper India, as to 

 those of British America, covered by terrestrial allu- 

 via, there are thousands of similar inland places in the 

 world, where the same facts must exist ; as it is most 

 certain that these deposits have been often confounded 

 with the proper tertiary strata. And these are the 

 cases also, where the alternations of marine and ter- 

 restrial remains especially occur; under circumstances 

 precisely the same as are now taking place on many 

 sea shores, and especially at the sestuaries of rivers. 

 To class these with other tertiary strata, is to place 

 an effectual bar to all knowledge or hope of order : 

 they must be ranked with alluvial formations; for to 



