of Determining the Elementary Electrical Charge. 221 



as much as possibl", in the experiment recorded in series No. 3 

 we used alcohol drops instead of water, pushed the plates 

 closer together, and changed the distance between the cross- 

 hairs. All of these observations on alcohol were exceedingly 

 satisfactory, although in this case we did not have the double 

 check upon the evaporation, since we had but two cross-hairs 

 instead of three. 



Series No. 5 represents two single observations taken under 

 conditions less favourable than the rest, and for this reason 

 this series has been assigned a weight of but one in the final 

 summary. 



Table. 



Series No. 1 (Bal. pos. water drops), 

 Distance between plates # 545 cm. 

 Measured distance of fall *155 cm. 



Volts. 



Time. 



Time. 





1 space. 



2 spaces. 



**2285 



2*4 sec. 



4*8 sec. 



2285 



24 sec. 



4*8 sec. 



**2275 



2"4 sec. 



4*8 sec. 



***2325 



2'4 sec. 



4'8 sec. 



2325 



2-6 sec. 



4-8 sec. 



*2325 



2-2 sec. 



4"8 sec. 



**2365 



2-4 sec. 



4-8 sec. 



2312 



2-4 



4-8 



Observer. 



Millikan. 



ii 



Begeman. 

 Millikan. 



Mean time for 155 cm. =4*8 sec. 

 155> 



< f 3 =3-422xlO-»X^?X 



l-i'l-i 



/•15oU 



Us; 



= 13-77 Xl°~ 10 - 

 .e=1385xl(T 10 4-3=4-59 xl0~ 10 . 



Series No. 2 (Bal. pos. water drops). 



Distance between plates '545 cm. 



Measured distance oi fall -155 cm. 



Volts. 



2365 



**2365 



*2365 



*2365 

 *2395 

 *2395 



***2395 

 2365 

 2365 

 2365 



2374 



Tone. 



Time. 



1 space. 



2 spaces. 



1-8 sec. 



4-0 sec. 



1*8 sec. 



40 sec. 



2-2 sec. 



3-8 sec. 



1 -8 sec. 



4'0 sec. 



2-0 sec. 



40 sec. 



20 sec. 



4 sec. 



2-0 sec. 



3-8 sec. 



1-8 sec. 



4'0 sec. 



1-8 sec. 



4 sec. 



1-8 sec. 



40 sec. 



1-90 



3-90 



Observer. 

 Millikan. 



;> 



Begeman. 

 Millikan. 



Mean time for *155 cm.=391 



980-3 w /-155\| 

 1452 



•3 /'155\i 



Y2 x [m) 



c 4 =3-422xl0 -9 > 



= 1S-25X10- 10 

 :e= 18-25-M=4 56 xl0~ 10 . 



