the Transmitting Antenna in Wireless Teleqraphy. 187 
TABLE III. 
Method of Direct Excitation. 









| Distance, in cms., of minima from free end of wire. 
) ) 
| Peel Se py ee 
| antenna, A. | B. e D. 
i | With cylinder | Withearth | With equal | Inductance 
| capacity. - connexion. wire. spool and earth. 
200 | (60), 153. | None. None. (60), 160. 
300 | 100. | None. None. | (90). None. 
400 | 120, 360. | (120), (205), | 105. None. | 80, 230, 380. 
None. | 
500 | 106, 280, 455. ‘| (120), 215. (125), 198. | (120), (200), | 
) (320). ) 
600 | 100, 290, (435), | None. | None. None. | 
| (545). 7 | 
700 110, 300, (580). | 100, 300, 500. | (120). None.) (58), (170), (280), 
Po None. | (420). None. 
800 | 100, (800), (518), (120). None. None. None. 
(650). ) 
900 | 90, 310,495. (200). None. _ None. | (140), (320), 
) _ (740). None. 
/ 1000 |(160). None. — (100), (220), (100). None.| (100), (220). 
) ) | (700?). | None. 

It is seen that the curves obtained with disposition A 
(fig. 11), are of a different type from those with the three 
other dispositions. In these latter there is always a gradual 
but decided drop of potential-variation from the free end of 
the wire, that is, the fundamental of the wire is very intense, 
though the curves show other oscillations superposed. With 
disposition A this strong fundamental is absent, and the 
minima present are undoubtedly due to the oscillations 
impressed on the wire by the condenser circuit. All through 
this series will be seen a minimuin occurring at approxi- 
mately 100 cms. from the free end of the wire, and in many 
cases one or two other minima spaced at approximately 
200 cms. apart. The same minima appear in disposition B 
with wire 700 ems. long, and C with wire 400 cms. 
The mean value of the wave-length is 404 cms., calculated 
as follows :— 
