OX THE ELECTRICAL PROPERTIES OE PURE SULPHUR. 
125 
enough as a whole to account for any serious diminution of the residual charge, as 
was ascertained by observing how the residual charge was held. The voltage of the 
residual charge was only about *3 volt in this case, and less in the former case—so 
that it is conceivably a case of galvanic polarization only. Against this, it may be urged 
that the residual charge increases with the time—strong evidence that the polarization 
is dielectric, not galvanic. In order further to test this conclusion 103 volts, instead of 
238'6, was applied for the same time (five minutes), and the residual charge, after one 
minute, was found to be *187 per cent, of the initial charge. A good many very 
concordant observations were used in obtaining these values, and there is no doubt 
about the residue being larger in proportion with the smaller voltage. This result is 
not in accordance with the results obtained by Bouty for mica condensers, which was, 
at all events, partly owing to the charge creeping over the mica edges. In our case, 
we cannot assert that the small residual charge observed by us was not due to the 
charge creeping over the sulphur surface. Since the residual is so small that we are 
unable to discover its origin by experiment, there is not much to be gained by specu¬ 
lation. We may, however, say that this film was probably a great deal more 
wanting in homogeneity than the perfectly soluble film, and that we expected a 
much larger residual charge in consequence. That such was not obtained, may either 
indicate that the possible explanation suggested by Maxwell does not apply in 
this case, and that we are actually in presence of the new kind of polarization he 
suggests, or that though the want of homogeneity is considerable, the variation of the 
ratio of specific inductive capacity to specific resistance, from point to point, is only 
small. 
As there is every reason to expect that the constitution of a mixed film will con¬ 
tinually change, owing to instability of the insoluble sulphur and the gradual 
tendency of monoclinic to pass into octahedral sulphur, the capacity was taken again 
in order to detect any change that might have taken place. This was seven days 
after the film was first made. 
The capacity of the condenser was found to have changed somewhat, more than the 
change of temperature would be likely to account for, temperature 21°*5 for both 
condensers, corresponding to a change of only ‘3° C. The capacity now was such 
that the balance changed from 1071 to between 1089 and 1090 with 40 Clark cells. 
This leads to a value of K of 4*247 as against 4T814 obtained before. There is no 
doubt about the film having undergone some change. The resistance was, therefore, 
measured (battery both ways) and found to be 5*018 X 10 35 C.G.S., with a voltage of 
262*8 volts and a galvanometer sensitiveness of 4*9 X 10 -13 ampere per micrometer 
division. The resistance has, therefore, increased also. There is no doubt that a real 
change has taken place, for the increase of specific inductive capacity precludes the 
possibility of the plates having separated. We attribute this to the conversion of 
the prismatic sulphur into octahedral, the only change to be expected, so that the 
specific inductive capacity is higher for the latter than the former. The film was 
