124 



A CONTINUOUS RECORD OF ATMOSPHERIC NUCLEATION. 



24. Remarks on the tables. Constructed graphically, the results of table 9 

 are irregularly below the coronal results. The results of table 10 are somewhat 

 smoother and in the main agree with the coronal data. Thus for the green 

 coronas (see Chapter VI, 29, table 17) 



coronal datum, g b p, n = 96,000, 



from table 10, g b p, n= 106,000, 99,000, 87,000, 86,000; mean, n = 95,000. 



or the mean values are about the same. In case of low nucleations and small 

 coronas the subsidence results are much too high as compared with the coronal 

 results, implying too small a value of the v of subsidence. 



The only explanation which suggests itself for this unexpected behavior is 

 the occurrence of acceleration in the motion of the fog particles. Accordingly 

 the following experiments with very small coronas (large particles) were tried 

 as a test. 



Normal corona with 5 = 2.9. 



Fall, / = 2 cm. time =15 15 13 16 16 



4 25 21 24 25 28 



6 32 27 30 30 



Thus V } = 



1.4 



Mean / = 15 

 25 

 30 



Ratio =15 



17 

 18 



indicating that the uniformly varied motion is only very gradually retarded by 

 the air resistance encountered. The following table contains similar data for 

 larger coronas, in none of which the evidence of acceleration is absent. 



TABLE ii. MEAN RATES FOR SUCCESSIVE DISTANCES OF 2 cm. EACH. 



These results rob the subsidence method of much of its trustworthiness 

 except when the particles are very small, when other difficulties step in: for 

 large coronas are not persistent in character. 



