COSMIC RADIATION — JOHNSON 



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ing zenith angles. From right to left the stations are arranged in 

 the order of increasing elevation and the rows are in the order of 

 the geomagnetic latitudes. In every case western intensities are 

 greater, though the amount of the excess varies widely with zenith 



FiODitE 4. — Stations where directional measurements bave been made. 



angles, latitude, and elevation. Progressing toward the Equator, 

 there is a definite trend toward higher asymmetries, and at each 

 latitude asymmetries are greater at the higher elevations. At each 

 station the asymmetry increases with zenith angle to a maximum 

 value at 50° or 60° and thence falls off again toward the hori- 



