450 G. Barns — Ions and Nuclei in Dust-free Air. 



small as well as large colloidal air nuclei are all successively 

 aggregated into larger particles. In other words, as the radia- 

 tion increases the whole air curve is bodily shifted more and 

 more and with change of form to the left into smaller super- 

 saturations, until eventually the persistent nuclei due to X-rays 

 actually appear, and require scarcely any supersaturation to 

 condense water vapor. 



4. Using an apparatus with a larger exhaust cock and ex- 

 haust pipes and therefore more rapid exhaustion, data were 

 obtained of which the following table contains examples. 



Table III- 



-Nucleation of dust-free air, energized 



or not. 



New apparatus, 



\%" stop 



cock, connections of inch 



gas pipe. 



Bar. 76-23. Walls of fog 



chamber 



■3 cm thick. Three horizontal partitions of 



wet cloth within 



chamber. 



















dp. 



s. 



n x 10- 3 . 





dp. 



s. 



n x 10~ 3 . 



Sept. 3 



44 



*7'7 



180 



Sept. 3 



19-6 



2*6 



5'2 



I. 



42 



*7'6 



175 





20-4 



4*9 



37 





35 



*7'6 



160 





21-0 



52 



43 





30-8 



*7-5 



137 





T~V 









26-1 



2-G 



62 





IX. 







24-3 



•7 



•2 



X-rays, 



D = 50 



cm from 



side. 







•5 



•1 





48-9 



J7-6 



190 





25-3 



1-4 



1-7 





43-6 



§8-0 



216 





26-1 



2-6 



6-2 





35-2 



|9-0 



240 





27-0 



3-6 



17 





30-8 



f9'3 



258 





27'6 



5-0 



46 





26*6 



f9'2 



229 





28'6 



5-4 



60 





22-8 



1*0 



137 





29*3 



6'3 



92 





21-5 



J7*3 



120 





30-5 



7-0 



125 





20-8 



||7'2 



100 





35-0 



7-7 



160 





19-5 



5-1 



39 





30-5 



*7-5 



136 





18-6 

 18-3 



1*1 



0? 



1 



0? 



II. Kadium tube 



added 



on side. 











Barometer 76 '05 (mean values) 





X 









43-6 



4-4 



43 



X-rays 



D = U 



cm from 



side. 





35-0 



5-4 



67 





18-9 



2-2 



2-7 





30*8 



5-6 



69 





20'0 



5-7 



54 





26-4 



5-6 



64 





21-0 



J7-4 



117 





24-2 



5-6 



60 





23-0 



tf7'3 



125 





22-8 



5-6 



57 





24'5 



f9'5 



195 





21-2 



5-6 



55 





29-3 **10'5 



290 





20-0 



4-1 



20 





35-0 **10-7 



320 





18*8 













43-7 



|| 10-3 



306 





19-0 













52-2 



§9*4 



240 





19-0 



•5 



•1 











The feature of these data is their steadiness in the lapse of 

 time. The curves have naturally moved bodily into lower 



* G' B P corona steadily repeated, 

 |GBP. § w P corona. 



but not quite clear. 

 II w y g. 



w o g 



f w r g. 



tfgyog' 



