1017 
6. In this we have not yet made use of the electrically sprayed 
mercury particles. These have given rise by their behaviour to the 
question of the subelectrons. EnreNnarr *) thought he had to con- 
clude from his experiments with this substance: electricity is not 
divided into quanta, or if it is, the quantum is much smaller than 
the electron assumed up to now. Among the opponents of this thesis 
especially ‘TArGonskI*) has tried to give an explanation of the phe- 
nomenon by assuming that the particles possess a much slighter 
density than that of mercury. This would result in a charge that 
was calculated much too small. Tarconski determines the spec. grav. 
of the grey layer which covers the wall of the vessel and the sur- 
face of .the mercury after repeated spraying, and finds for it 7.3. 
He derives from this that the mean density of the sprayed particles 
is much smaller still. He does not determine, however, the density 
of the drops themselves. I think I have found a means in my expe- 
riments to determine it directly, though it be not with very great 
accuracy. The particles were sprayed in my experiments in ordinary 
air, in those by EnreNHaFT and TarGonski in dry nitrogen. 
With the aid of the known value of ¢ the corresponding value 
of a can be read from fig. 4 when we assume that the curve 2 is 
TABLE IL 
Nitmibers| 708 the t. Ben fe p calc. | 
charge | | 
146 PS Wo el al oe a 
: 94 | Bor Tee betes 2 
Weken — 43.99" |t. ia | 1.85 |) 12 
Te | 4.06 bte | 1.90. | tt 
141 ES 4.28 | 1.07 | 1.80 | 12 
150 an bods [1407] 1.85] 016 
110 ker |A ET | 11 
138 aah A Te |, Ore Doren oie 
117 SER PA ERM CMe ac) ete 
123 steel 801 [70.99 | 14604 | 10 
doe face hg Ook.) AO) EE Bee al 
149 — | 6.46 | 0.77. | 1.40 | 12 
1) PF, EHRENHAFT |. c. 
2) A. TARGONsKI, Arch. de Genève, 4, 41, 1916, p. 207, 
