136 Mr. C. A. Chant on the Variation of Potential along 
same as that of an equal length of straight wire. It was put 
in this form, however, through a desire to have the arrange- 
ment as nearly as possible like that used in actual practice *. 
lt will be seen that 75 cms. of the closed condenser circuit 
are a part of the open antenna circuit. According to Braunt 
the larger this portion of the condenser-circuit included 
in the antenna is, the better will be the effect, and it performs 
a role other than simply as a portion of the antenna. 
Four different arrangements were employed to balance the 
antenna wire :— 
A. The cylinder capacity used in the experiments with 
the Braun transmitter was connected to the condenser 
circuit at a, the length of the wire ab being 40 cms. 
Thus the length from this capacity to the end D 
of the antenna was 40+ 75=115 cms. 
B. The point a was joined to earth (the same as above), 
the wire ab being 25 cms. long. In this case the 
length of the conductor between earth and D was 
75 +25=100 cms. 
C. To a was attached a wire precisely similar to that used 
as antenna. Here the two wires were joined by 
75 cms. of the condenser circuit. As before, the 
balancing wire was drawn up in a vertical direction 
towards the ceiling. 
D. The same as B, except that between a and 06 an 
inductance-coil was inserted. This coil was of heavily- 
insulated wire, the conductor having a diameter of 
2 mms., the diameter over all being 7 mms. There 
were 4 turns lying close together, with a total length 
of 82 cms. The object was, of course, to see if there 
would be any evidence obtained of the wave-length 
being increased by inserting this inductance-coil at 
the base of the antenna. In this case the length of 
the conductor from D to earth was 75+82+425 
=182 cms., though the inductance-coil itself would 
probably be equivalent to 200 ems. of straight wire. 
A view of the results obtained on using wires varying 
in Jength from 200 to 1000 cms. and the four experimental 
dispositions just described is given in Table III. and the 
curves of figs. 11, 12, 13, 14 (Pl. XIII). 
* Several good illustrations of the latest apparatus are given in 
C. Arldt, Die Funkentelegraphie, pp. 48-51 (Leipzig, 1903). 
+ F. Braun, Ann. der Physik, viii. p. 199 (1902). 
