62 A CONTINUOUS RECORD OF ATMOSPHERIC NUCLEATION. 



TABLE I.— SECOND SERIES. n,= 190000; a=.o6i. 



o 

 I 

 2 

 3 

 4 

 S 

 6 



7 

 8 



9 

 10 

 II 

 12 

 13 

 14 



'5 

 16 



Corona. 



b'b- 



g' 



yob 

 w c g' 

 gb- r 

 ygobg 

 wc g 



g'!b-|P 



wcg 



w brb'g'r 



corona 



»' = 2 75 53. 



327 



157 



59 



48 



41 

 24 



17 



12 



6 



3 

 I 



;i" = 370 53. 



440 

 212 



79-9 

 65.1 



SS-i 

 32.6 



237 



17-3 



9.0 



2-5 



1-3 

 ■4 



.¥27 (i-fj 



(2.84) 

 (2.19) 

 (1.69) 



(1-3°) 

 1. 000 



•751 

 •557 

 •398 

 .280 

 .196 

 .130 

 .083 

 .050 

 .027 

 .on 

 .C02 



182 

 207 

 181 

 T89 

 230 



540000 



416000 



321000 



247000 



190000 



143000 



106000 



75600 



53200 



37200 



24700 



15800 



9500 



5100 



2100 



400 



o 



d = .021 

 w-1/3 



.000256 

 278 

 304 

 331 

 362 



398 

 440 

 492 



555 

 623 



715 



830 



980 



.001200 



1630 



2850 



' Gap in coronal sequences probably due to accidental delay. 

 Timed fog intervals desirable. 



Similar difficulties at end of series. 



METHOD OF REDUCTION. 



8. Constants of the geornetric progression. — To determine whether the 

 factor of the geometric progression of successive nucleations, z, was to be com- 

 puted isothermally or adiabatically, a series of direct temperature measurements 

 was deemed necessary. These were made by aid of a thermocouple of ex- 

 tremely thin wires (.007 cm. in diameter), of copper and german silver. The 

 junction within the receiver was not soldered, but the flexible copper wire 

 looped once around the other. In this way the variation of the instantaneous 

 air temperature in the receiver could be closely followed. It was necessary to 

 use a sensitive astatic galvanometer, and the measurements are thus subject to 

 the fluctuations of the earth field. As it is the immediate purpose of these data 

 to determine about how soon the isothermal conditions are re-established by 

 radiation from without, the irregularities are of little consequence. 



Table 2 contains three series of results, the upper end of each row corre- 

 sponding to the period of exhaustion, the lower to that of (slow) refilling. 

 Readings were taken in intervals of half a minute. The table shows that after 

 the lapse of one minute following the sudden exhaustion the temperatvu-e has 

 been regained to within a degree. As the coronas can hardly be observed and 

 measured within this time, the exhaustion ratio may be computed. isothermally. 

 I have therefore computed the density ratio of nucleation p/ p' = n/n', before 

 and after exhaustion, as follows. 



Since p = RpB in the usual notation of Boyle's law, and p = P-p' where P 



