158 



OCEAN ATMOSPHERIC -ELECTRIC RESULTS 



a value of 1.2 ion-pairs per cc per second for the free 

 atmosphere near the ocean surface. These values will be 

 recognized as in satisfactory agreement with the work of 

 other investigators in cosmic rays. 



In tables 3 and 4 the distribution of penetrating radi- 

 ation values is shown for the Atlantic and Pacific oceans, 

 respectively. In both tables the values fall chiefly in the 

 range of 2.40 to 3.20; in table 3 the values in this range 

 are 77 per cent of the total, and in table 4 they are 93 per 

 cent. The greater scatter of data for the Atlantic Ocean 

 may be due to the fact that the work in that ocean was 

 done in the early part of the cruise when observational 

 procedxires perhaps were not so well established as later. 



For the Pacific Ocean data 75 per cent, or three out of 

 every four values, lie within the narrow range of 2.60 to 

 3.10 ion-pairs produced in the instrument per cc per 

 second, for which corresponding values of ion production 

 in the atmosphere would be 1.1 to 1.6 pairs per cc per 

 second. These values, and others given earlier in this 

 paper as representing the rate of production of ions in 

 the free atmosphere, are of acceptable magnitude, indi- 

 cating that the value of residual ionization of 1.5 ion- 

 pairs per cc per second for apparatus 1, although derived 

 from few data, is close to, if not precisely the correct 

 value. 



Table 2. Penetrating radiation measurements of cruise VII in the Atlantic and Pacific oceans, 



grouped according to geographic latitude 



Ocean 



60.0- 

 64.1 N 



50.0- 

 59. 9N 



40.0- 

 49.9N 



30.0- 

 39. 9N 



20.0- 

 29.9N 



10.0- 

 19. 9N 



0.0- 

 9.9N 



0.0- 

 9.9S 



10.0- 

 19.9S 



20.0- 

 29. 9S 



30.0- 

 40.4 S 



*R = ion-pairs produced in apparatus per cc per second, 

 number of observations in each group. 



b Numbers in parentheses indicate 



Table 3. Distribution of Atlantic Ocean values of penetrating radiation from cruise VII 



for different latitude belts 



