408 C. A. Chant — Reception of Electric Waves. 



that there is one law for the wires 6 meters long and upwards, 

 another for those shorter than 6 meters. VVith the former 

 there is a minimum in the neighborhood of 220 cms from the 

 free end. For the wire 1000 cms long it appears at 254 cms from 

 the end, but this is* not so sharply defined as the others, though 

 five sets of readings were taken to obtain this curve while 

 three were usually made for the others. 



This appears to be a quarter-wave-length of an oscillation 

 impressed on the wire, but not that shown on the transmitter. 

 Again, if we assume that there is no displacement of the 

 nodes upon reflexion from the free end, the maximum should 

 be found at a distance twice as great from the free end. But 

 such is not the case. There is a distortion of the oscillation, 

 though for what reason it is not evident. 



An attempt was made to see what length of the wire was 

 equivalent to the receiver connections, i. e., to the portion 

 from a to E, including E. In doing this the transmitting 

 antenna was 4 meters long, arranged as usual. Opposite and 

 parallel, at a distance of two meters, a wire 4 meters long was 

 stretched, to act as the receiving antenna ; and then, in place 

 of the receiving apparatus, a long wire was attached at a and 

 drawn vertically upward, to prevent, if possible, inductive 

 action between this wire and the transmitting antenna. At 

 first this wire was 9 meters long, that is, the entire length of 

 the wire was 13 meters. The horizontal portion only was 

 explored. Then the vertical wire was shortened to 8 meters 

 and the horizontal portion again explored. This process was 

 continued, shortening the vertical wire one meter at a step, 

 until only the horizontal one remained. The results are shown 

 in Table II and the curves of figure 4. 



Table II. 



Total length of wire in 

 meters. 



13 



12 



11 



10 



9 



8 



7 



6 



5 



4 



Distance, in cms., of 

 minima from free end. 



260 



255 



225 



210 



210 



207 



190,304 



304 



253 



202 



Highest reading, i. e., at 

 free end. 



42 



51 



51 



41 



28 



28 



57 



92 



85 



T7 



An examination of these shows that the wire 6 meters long, 

 i. e., with 2 meters vertical, behaves like the 4-meter antenna 

 when joined to the receiving apparatus, or that this apparatus 

 behaves like 2 meters of wire. This method of substitution is 

 not entirely free from objection, but I know of no better. 

 Somewhat later it will appear from the same method that the 

 cylinder E (fig. 1), is equivalent to about 80 cms of the same 



