﻿Electricity on Streams of Water Drops. 153 



(1) Figs. 8 a, $b, 8 c, from the streams just above the 

 nozzle in the cases when the inductor was charged to zero, 

 4-80 volts, and +720 volts. The velocity o£ the stream was 

 unfortunately too great to give clear cat drops in these cases, 

 but sufficient is shown to bear out the conclusion illustrated 

 better in figs. 1 and 2, viz., that there is no apparent difference 

 between the sizes of drops as they break from the uncharged 

 and charged streams. The absolute alignment of the drops 

 in the 80 volt case may be noted, while both of the other 

 streams give indication of instability. 



(2) Figs. 9 a, 9 b, and 9 c show photographs of the 

 streams higher up than the preceding. Fig. 9 a shows the 

 uncharged stream (of fig. 4) just as the scattering begins ; 

 there are indications of the breaking up of the larger drops 

 which may be due to collisions. Fig. 9 b shows the com- 

 plete stream for the inductor charged at +80 volts (similar 

 to the case of fig. 5). Three characteristics may be noted : 



(1) Variation in the size of the drops in the stream : 



(2) absolute alignment of the stream up to the top of its 

 course ; and (3) no indication of coalescence or collision 

 until the top of the stream is reached, that is, until succes- 

 sive drops have completely gained on their neighbours 

 preceding (the stream was directed slightly out of the 

 vertical). When the inductor -tube was charged to 

 + 720 volts the arrangement of tbe drops is shown in fig. 9 c, 

 The exposure was made at the point where the stream (see 

 fig. 7) just begins to scatter. Up to the point where the 

 scattering takes place we have the same appearance as that in 

 9 b in regard to variation in size of the drops and align- 

 ment of the stream. 



(3) Figs. 10 a and 10 b are photographs of the very tops 

 of the streams charged by the inductor at +240 volts and 

 + 720 volts respectively (see figs. 6 & 7). There is a greater 

 proportion of small drops with the higher voltage than with 

 the lower, from which we might conclude, keeping in mind 

 the foregoing photographs, that there is a splitting up of the 

 large drops at the higher voltage. Of course the higher the 

 charge on the drops the greater the disintegrating force and, 

 although the voltage of the drops is much below the limit 

 set by Rayleigh* for instability, nevertheless with the motion 

 which the particles have and the influence of the presence of 

 other charged drops, it is conceivable that the larger drops 

 may be split up under the influence of the electrostatic 

 tensions over their surfaces. There also seems to be a 



* Phil. Mag. [olxiv.p. 184. 



