100 



DYNAMIC METEOROLOGY AND HYDROGRAPHY. 



110' I"" 90 *W 



1000-2000 dvn.meters 



Fig. 16. Field of mass, Svpt. _'.">, I 898, represented by charts giving the 

 average density ( 10~ 5 ton/m' ) of the air between level sur- 

 faces, or the difference of pressure between these surfaces 

 in m-bars. 



Fig. 15. Field of pressure, Sept. 23, 1898, represented by isobaric charts 

 giving the pressure in level surfaces in m-bars. 



