A CONTINUOUS RECORD OF ATMOSPHERIC NUCLEATION. 



the shifting attending the standardization of n and d. If the horizontal position 

 of the cusps be taken from the figure as 5=2.7, 4.2, 5.6, 8.3 in curve i on the 

 left, and 5 = 2.8, 4.1, 5.6, 8.3 in curve 2 on the right, the mean ratios are 2, 

 3, 4, 6, so that 5= 1.4 or <p= i 18' repeats itself. Since d = .0029/5 nearly, the d 

 ratios should be as 1/2, 1/3, 1/4, 1/6. The figure shows roughly in curve i 

 io < y=noo, 710, 540, 400, and in curve 2, io 6 d=-io5o, 740, 550, 350, the means 

 of which values are in the ratio of 6, 4, 3, 2, as nearly as can be expected, the 

 data being multiples of .00018 cm., here as above. The presence of a period 

 between 4 and 6 is not in evidence. 



MISCELLANEOUS EXPERIMENTS WITH THE DEEP VESSEL. 



21. Measurement to the edge of the white disc. Before citing data obtained 

 from measurements of the aperture of the disc, it is desirable to reduce the 

 preceding data, 5 (aperture to the outside edge of the first ring) to 5 ; (aper- 

 ture to the inside edge of the first ring) by direct experiments. This is done in 

 the next table (9). The relation within the normal region is practically linear 

 and 5 ; /5 = .76. 



Careful inspection of the coronas seen with electric light shows that even 

 when normal the edge of the white disc shades off through y, o, br, etc. There 

 is no real demarcation of the white disc, but the r 1 edge is rather the beginning 

 of a diffraction cycle in which (counting from the outside inward) r, o, y, merging 

 into white, appear, and when the higher coronas are reached the missing g, b, v 

 become evident in their turn. 



TABLE 9. OUTSIDE AND INSIDE DIAMETERS OF THE RED RING. DISC, w w' y' 

 br' vp' b g y' r; EDGE, a w y HAZE. MEAN RATIO, S,/S O = .T]. 



Measurements of s a before and after j. 



Table 9 shows that if ds ( . = . 00291 (subsidence), then 

 a ; = dsj = . 00291 X. 77 = . 00223 and n=(6w/77-a?) 



