THE STRUCTUKE OF THE NUCLEUS. 



97 



whence s^ = .97 cm. lu.-iy be taken as the mean result, at the anterior and posterior 

 tangent planes of the I'eceiver, 1.05 and .95 meters, respectively. Hence, since 

 Sg X .0032 —sd, (l=.OOSl/s cm., from which the columns under d, showing the 

 diametei's of the coronal particles, are computed. As a rule the diffi'actin"- water 

 globules of the coronas ai'e about as large as lycopodium spores, the supei'saturation 

 being high and the number of nuclei relatively few. 



The columns mai'ked it contain the nucleation, i. t., the nundjcr of particles 

 generated liy shaking, per cub. cm. These are computed from d and the total 

 amount of precipitation |)cr iniit of volume, as set forth in i< (;. 



A nund)er of miscellaneous data contained in the tables will ex[)lain them- 

 selves. Thus d/i/dt are the time I'ates at which the nuclei vanish, or the deciement 

 of the number per minute; dn/dS shows the average number generated in one 

 shake or jerk u[) and down ; etc. 



A series of values of h, the absorption velocity, are finally added from com[)u- 

 tations given below. The meaning of k is as follows : It is supposed that the loss 

 of nuclei in the lapse of time is due to their absorption at the walls of the spherical 

 receiver (radius, ^ = 15 em.). If this loss is a deci'ement from the contents of the 

 receiver as a whole — {ATrJi^/-i) (iln/dt) — h i^Ji^ n, whence 



M=«„l()-3^'^(log^)/^, 

 and it is therefore sutficiently api)roximate to write, k — 11.5 (S log>i./,^(). As the 

 results are inevital)ly crude, very little confidence can be felt in the minor vai'iatious 

 of k, these being introduced by differences in shaking. The order of values 

 obtained, however, presents a wide sweep and is of gjeat interest. 



TABLE I.— PROPERTIES OF NUCLEI DUE TO SHAKING DILUTE SOLUTIONS 

 OF HCl; RECEIVER 3 METERS FROM LIGHT AND i ME PER FROM 

 GONIOMETER; ARM OF SAME 30cm, fl' = .oo3i/.f. 



Faint corona, forms gradually. 



' Violent shaking. 



