On the Comparative Level of Lakes and Seas. 335 



gineers have thus connected these points with those determined in the 

 Tyrol by the Austrian engineers, so furnishing the following results, 

 starting from the Mediterranean : — 



Metres. 

 == 670.00 1 

 = 662.00 J 

 = 1636.33 \ 

 = 1627.58 1 

 = 2103.80 » 

 = 2394.68 i 



Difference = 8.76 



Difference = 9.12 



Altitude of Kumenberg above the Mediter- ) _ /»-« rw^ \ Metres, 



ranean at Marseilles, ... J " ^'^'^ \ Difference = 7.63 



The Austrians give it, above the Adriatic, 



Altitude of Fr.a8tenzersand above the Medi- 1 

 terranean at Marseilles, . . . j 



The Austrians make it, above the Adriatic, 



Altitude of the Fundelkopf above the Medi- 1 

 terranean at Marseilles, . '. . ) 



The Austrians give it, above the Adriatic, 



Hence the mean height of the Adriatic Gulf above the Mediterra- 

 nean at Marseilles, ....... 8.50 



The Swiss engineers make it in reference to the ocean, . . =763 



'^ M. Delcros is persuaded that this difference between the levels 

 cannot exist. Admitting a filling of the Adriatic, from the feeble tides 

 which occur, and from the counter-current that is well known, these 

 effects together cannot amount to 7 or 8 metres. He has been assured 

 that the Swiss engineers, in discussing the partial results inserted in the 

 hypsometry of Austria by Colonel Fallon, have been led to reduce this 

 pretended difference of level from 8 metres to 2. He is not yet informed 

 upon what grounds this reduction is made ; but he taies the liberty of 

 expressing a hope that the Austrian Government will direct that the 

 most southern points of Switzerland and Bavaria shall be linked in a 

 manner more satisfactory and accurate with the Adriatic."* 



It has appeared to me important to collect in this work all that we 

 know at the present time, concerning the comparative hydraulic hypsometry 

 of the waters which belong, and those which do not belong, to the same 

 surface of level. Physical geography can make progress only by grasp- 

 ing the results already obtained, by discussing the bases of numerical 

 elements, and mounting up to those general views which alone give dig- 

 nity and life to the sciences.t 



• M. Delcros supplies the following results of the correction of the triangles of 

 Bavaria :— 



1. Summit of the tower of Notre Dame of Munich, 

 Pavement of the same church, 



2. Peissenberg, at the surface, pavement of the church, 



3. Benedictenwand, summit of the mountain, 

 4 Wendelstein, summit of the mountain, 



Metres. 

 615.67 

 518.67 

 985.14 

 1798.96 

 1843.60 



{Note^ September 1841.) 



t From Humboldt*8 Atie Centrale, 1843, vol. ii., p. 301 . 



