^92 Geological Imtructions for the 



ever rich this part of our work may appear, it will occur to any 

 one acquainted with the subject, that it should be considered 

 only as a commencement and basis for future investigation. 

 We have done what was indispensably necessary for a chart 

 constructed upon the scale which we have adopted. We hope 

 that measurements will yet be obtained which will be more ex- 

 act, more extensive, and more numerous than our own, and that 

 more precise methods of calculation will be employed, when 

 several as yet unsettled questions have been determined (such 

 as that of a real physical libration), and the complete accuracy 

 of various elements shall have been ascertained. What relates 

 to the measurement of the heights, is necessarily the part which 

 is most defective as it regards the exactness of the results ; and 

 it is here the greatest quantity of work remains to be done. 

 We may, on this point as well as others, at least offer this assu- 

 rance, that we have never presented results whose precision and 

 harmony were the result of the suppression of less concordant 

 observations. We have principally endeavoured to take for 

 our model, so far as it was possible, the comparative method 

 followed by Ritter in his last work descriptive of our globe. 

 We hope we have succeeded in preparing a comparative Geo- 

 Selenology, for future enquirers, or a parallel of these two 

 neighbouring worlds, which, in our opinion, ought to be the 

 chief object of pursuit in our ulterior labours. It is thus only 

 that these two sciences, which are even still in their infancy, 

 although in different degrees, can be elucidated and advanced 

 either individually, or in their respective bearings." 



Geological Instructions^ prepared by M. Elie de Beaumont for 

 the French Scientific Expedition to the North of Europe,'^ 



If it were the sole object of a scientific expedition, such as 

 the one we are now about to send to the north of Europe, to 

 obtain more information about the countries to be explored, 



• The object of this expedition, in which the King of the French takes so 

 lively an interest, is to collect new observations in Denmark, Sweden, and 

 Norway, the North Cape, and Spitzbergen, destined to complete those al- 

 ready made by the French naturalists and philosophers, during the late expe- 

 dition to Iceland. 



