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On the Comparative Level of Lakes and Seas, as the Caspian, 

 Lake Aral, Black Sea, Red Sea, Mediterranean, Lake Ti- 

 berias, Dead Sea, Atlanticy Pacific, ^c. By I3aron 

 Alexander von Humboldt. 



Tho Caspian Sea has presented two problems which have long been 

 subjects of discussion, — the problem of its isolation, and that of the 

 relative height of its mean level ; and there has been a similar fluctuation 

 on both these points. Inasmuch as, by the assiduous labours of Messrs G. 

 Fuss, Sabler, and Sawitsch, the height of the waters of the Caspian was 

 perfectly ascertained in the year 1837, we might pass in silence the 

 attempts which were made by means of barometrical measurements. I 

 wish, however, to record here some of the results which, for 60 or 70 

 years, most engaged public attention. 



Ckappc'^ found from the barometrical observations made by Dr Lecre 

 at Astrakhan, from the years 1732 to 1749, that the Caspian was depressed 

 51 toiees. This result he designated as '* evidently absurd." 



Inochodzow, in comparing the mean barometric heights of Kamychine, 

 a small town in the government of Saratov (means deduced from ob- 

 servations from October 1770 to August 1774), with the corresponding 

 barometric means of St Petersburg, concluded from tliis comparison, that 

 Kamychine (lat 50° 5'), upon the banks of the Volga, is 171 French 

 feet, (28.6 toises), below the level of the surface at St Petersburgh.l 

 There is a difference of 4° of latitude between Kamychine and the 

 mouth of the Volga ; and there is 10° between Kamychine and St 

 Petersburgh. It is very likely that a remark respecting the depression 

 of the basin of the Caspian, which is to be found in the celebrated work 

 of the Abbe Raynal upon the colonies, is grounded upon his cognizance 

 of the barometric calculations of Inochodzow. This eminent Russian 

 philosopher mentions that, previous to his time, Chretien Mayer, in a 

 memoir regarding the transit of Venus (p. 316), had valued the negative 

 height of the Caspian at 101 feet (17 toises), grounding his calculation 

 upon the barometrical observations of the traveller Lerche, It is almost 

 superfluous to point out, that this coincidence, with the first provisional 

 result derived from the grand trigonometric levelling of 1837, is alto- 

 gether accidental. In fact, it is in hypsometry as in the determination 

 of diflerent astronomical positions. When a point has for a long time 

 oscillated in our charts from north to south, we always find some one or 

 other ancient chart which indicates the true latitude, in agreement with 

 the result of the latest and most difficult operations. Pallas| preferred 



* Toy. en Sib^e, T. ii. pp. 487-491. 



t Nov. Acta Acad. Petrop. T. xii. p. 50C, 1801. 



X Reise, T. iii. p. 316. 



