DISTRIBUTIONS OF NUCLEI. 



75 



whether large or small nuclei are in question. One should expect these 

 conditions to depend on the size of nuclei; but (as the data show) even 

 though larger numbers of nuclei are certainly present, they are devoid 

 of efficiency beyond the limit. 



Fig. 35. Nucleation (n, in hundred thousands of nuclei per c. cm.) observed in dust- 

 free air and in energized air at different exhaustions. dp = p-p 2 . 2-inch and 4-inch 

 pipes and perfected apparatus I and II. Tables 23, 24, and 25. Ions in No. I con- 

 sistently in excess. 



Table 24. Fog chamber and vacuum chamber as in fig. 34, joined by 2-inch pipes, 

 2^-inch plug stopcock. dp = p - p 3 . Final series for comparison. 



* Correction for barometer made as explained in Chapter VI. 



