488 On the Theonj uf the Electric Residue in t/ie Leyden Jar. 



the lever descended could be regulated by the height of its fall, 

 or bv a moveable weight made to act against cords of vulcanized 

 caoutchouc. Without doubt a greater stability in the indications 

 of this instrument would be obtained by using a heavier magnet, 

 wliich would involve, however, a small increase in the other 

 dimensions. Even with these dimensions the multiplier is an 

 excellent electrometer for currents of discharge, provided it be 

 properly retarded when very strong charges are employed. 



Such an apparatus may be used with advantage to determine 

 the proportion in which electricity has divided itself between two 

 Leyden jars. \ sine-electrometer is connected with one jar 

 only, and as soon as the former indicates a certain deflection, the 

 latter is discharged through the multiplier. A second jar is 

 then connected with the first, and both are simultaneously dis- 

 charged as soon as the sine-electrometer has attained its former 

 position. If in the first case the needle of the multiplier be 

 deflected to an angle a, and in the second case to a-|-/3, then by 

 equal tension on the knobs, the quantities of electricity in the 

 two jars will be as « to /3. In general, instead of the angles « 

 and /3, the number of scale-divisions which are deflected into 

 the field of the telescope may be taken. 



In Appendix I. we have described a method for finding the 

 proportion in which the charge divides itself betw^een two jars 

 by means of the sine-electrometer alone. This method suffers 

 from the disadvantage of the charge in the battery being change- 

 able. When a part of the charge is transferred to the single 

 jar, some time must elapse before the electrometer can be read- 

 justed for measurement. At first the charge imparted to the jar 

 appears on this account too great, because during this time, 

 besides the loss of electricity in the air, a residue will also have 

 formed itself; afterwards it appears too small, because the residue 

 already formed is too great to be detained by the remaining 

 charge in the battery, and as a consequence it is partly set at 

 liberty before the electrometer can be readjusted. The present 

 method is free from such disadvantages. In order to show its 

 exactitude, we will give the numbers which determine the pro- 

 portion in which the charge distributed itself between the jar F 

 mentioned in Appendix I., and the battery B of five jars. 



Deflection of the needle in the multiplier in scale divisions. 



By B alone. By B and F connected. 



■ 66-3 79-5 



66-5 79-6 



66-5 79-4 



66-2 79-2 



Mean 66-4 J2:^ 



Mean 79-5 



