316 Report on a Manuscript Work of M. Andre. 



7th, To follow minutely their different strata throughout 

 their whole extent, whatever may be their doublings, incli- 

 nations, ruptures, and slepings; and also to determine what 

 countries belong to one and the same formation, and what 

 others have been formed separately. 



Sth, To follow the horizontal beds and those which are 

 inclined in one or different ways, to determine if there is any 

 relation between the greater or less constancy in their hori- 

 zontal position, antiquity, or nature. 



9th, To determine the valleys in which there-entering 

 and saliant angles correspond, and those in which they do 

 not ; also those in which the strata are the same on both 

 sides, and those in which they differ, in order to discover if 

 there is any relation between -these two circumstances, and 

 if each of them taken apart has any analogy with the na- 

 ture and antiquity of the strata composing the heights which 

 limit the valleys. 



All these points are necessary to its elucidation, if we 

 wish to make geology a body of doctrine or a real science, 

 independent of every desire which we may have to find an 

 explanation of facts. We dare affirm that there is not one 

 of those points on which any thing absolutely certain is yet 

 known, every thing which has hitherto been advanced 

 being more or less vague. The greatest part of those who have 

 treated of such subjects, have considered them rather as they 

 answer, d their system, than according to impartial observa- 

 tions. ' . 



The fossils alone, singly considered, may yet furnish matter 

 for the study of 30 years to several industrious philosophers; 

 and iheir connections wiih their strata will still require as 

 many more years of travel, of boring, and other arduous 

 researches. 



What service would not a society such as ours render to- 

 the natural sciences, if it succeeded in directing to these 

 long, laborious, but determinate researches, those persons 

 with an ardent desire of knowledge, who are now likely to 

 be led, by the contagious example of many men of merit, to 

 the adoption of systems so easily created and so flattering to 

 vanitv ! The work of M. Andre, examined according to 



these 



