WHOLE VOL. 



LAT. 40 N. 



551 



SEA-LEVEIv TRESSURE AT 10" INTERSECTIONS 



Lat. 40° N. Long. 90° E. 



950 mb. + 



Date Jan. Feb. Mar. Apr. May June July Aug:. Sept. Oct. Nov. Dec. Year 



1929 



78.8 



75.5 74.7 CO. 4 63.5 



56.3 57.1 60.0 63.7 72.3 76.3 79.2 



Mean 80.0 76.3 71.4 64.9 61.5 54.8 52.8 66.1 63.0 70.7 76.3 79.7 



68.9 



67.8 



Mean 82.3 78.6 72.6 65.5 61.4 64.9 63.4 66.3 64.4 71.8 77.4 81.4 68.8 



19 



