400 



SCIEMTinC NEWS. 



SCIENTIFIC NEWS, 



Geographical 

 researches. 



A Report of the IVamactions of the Claffs of Mathema- 

 tical and Physical Sciences of the National Institute of 

 France^ for the preceding Year, was made at the public 

 Meeting of the 7th of July last, of which the following 

 IS an'itbridgment. 



(Concluded from p. 337.) 



JL O these geometrical considerations respecting the 

 figure of the earth the reporter obseryes, that the order 

 of connection would naturally direct him to the geogra- 

 phical researches on the extensive plain of the interior of 

 Africa, by Lacepede ; upon Persia, and the communica- 

 tion between the Caspian and the Black Seas, by Oli- 

 vier ; but as these memoirs more particularly belong to 

 physical science, and as such have been analized by Cui- 

 vier, he passes to the consideration of M. Raymond's 

 memoir upon the Admeasurement of the Heights of 

 Mountains by means of the Barometer. 



It was remarked in the Report of 1805, that there 

 was scarcely one five-hundredth part of difference between 

 the barometer, the coefficient of La Place for calculating the heights of 

 mountains by barometrical observation and that which 

 M. Raymond has deduced from numerous observations 

 of this kind made in the Pyrennees. New researches 

 have entirely obliterated a difference which might be at- 

 tributed either to the barometrical observations or to the 

 earlier experiments on the respective weights of air and 

 mercury which M. La Place had used in his computa- 

 tions. M. Biot has lately repeated these experiments^ 

 with the utmost precaution ; from whence it results that 

 the coefficient must be diminished very nearly one five- 

 hundredth, and the methods perfectly agree together. 

 , . On 



Measure of 

 heights of 

 mountains by 



