
Marcu 10, 1923] 
NATURE 
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length for sympathetic resonance. Thus I obtained 
_ the phenomenon of electric nodes and loops, due to 
- the production of stationary waves by reflection at the 
distant end, and in my own mind thus verified Max- 
well’s theory. (I gave a brief account of this work, 
_ with calculations of wave-length, in The Electrician for 
September 21, 1888, page 623. Many other passages 
of early history can be found in the same volume about 
that date. It was an important year.) 
Transmission along wires popularly sounds different 
from transmission in free space, but it was well known 
to me that the process was the same, and that the 
_ waves travel at the same speed, being only guided by 
the wires, much as sound is guided in a speaking- 
tube, without the velocity of transmission being to any 
important extent altered. The theory is given near 
the end of my paper—an important one as I think, 
and as Silvanus Thompson agreed—in the Philosophical 
Magazine for August 1888, where the experimental 
production of much shorter waves is also foreshadowed. 
The beginning of my experiments was reported to 
_ the Society of Arts in April 1888 ; they are recorded, 
as said above, in the Phil. Mag., and they were more 
completely described orally at the British Association 
at Bath that year. (See the Electrician, vol. 21, pp. 
- 607-8, September 1888.) 
In that year, also, I heard for the first time of 
Hertz’s brilliant series of experiments, where, by the 
use of an open-circuit oscillator, he had obtained waves 
in free space, and by reflection had also converted them 
into stationary waves and observed the phenomena 
of nodes and loops, and measured the wave-length. 
Attention was directed to these experiments of Hertz 
__ by FitzGerald in his presidential address to Section A 
of the British Association meeting at Bath in 1888. 
No wonder they interested him ; for they showed that 
his method of utilising the oscillatory discharge of a 
_ Leyden jar was effective ; and, to the surprise of all 
of us, including Hertz himself, that the waves from an 
opened-out condenser had sufficient power to generate 
sparks in an insulated conductor upon which they 
impinged ; the detecting conductor, as generally used 
by Hertz, being in the form of a nearly closed circle 
with a minute spark gap at which the scintilla appeared. 
The radiating power of even a small Hertz oscillator 
was calculated by me in a subsequent paper (Phil. 
Mag. for July 1889, p. 54), and was found to be 100 
horse-power, while it lasted. The duration was excess- 
ively short, for, at that rate, practically all the energy 
was expended in a single swing (about the roo-millionth 
of a second), but its power of producing little sparks 
was explained. 
This work of Hertz was splendid. He was then pro- 
fessor at Carlsruhe, still quite a young man. He had 
been trained under Helmholtz; and I had made his 
personal acquaintance in Berlin when I went to call on 
Helmholtz in 1881, on a tour of the universities of the 
Continent. He was then Helmholtz’s demonstrator, 
and was thought highly of by that great master. He 
could speak English, and was very friendly. I did not 
see him again till some time after the publication of 
his great discovery. 
__ Hertz was not at that time fully acquainted with 
Maxwell’s theory, although he knew his equations better 
than any other German except Helmholtz. Maxwell 
NO. 2784, VOL. 111] 
had not then made any serious impression on the 
Continent. Even Hertz does not seem at first fully to 
have realised what he was doing, and did not use the 
words “electric waves.” That title was attached to 
his subsequently translated book at the suggestion of 
Lord Kelvin. He spoke about the out-spreading of 
electric force; somewhat as Joseph Henry had done. 
That was the title of his book. He worked out the 
phenomena he observed with extraordinary skill, both 
experimentally and mathematically, rapidly perceiving 
that Maxwell’s theory could be applied to them, and 
that it might be elaborated in detail so as to include the 
whole of his phenomena. He it was who drew those 
accurate diagrams of the genesis of the waves, showing 
what is happening near the oscillator at every phase— 
diagrams which now appear in most text-books and of 
which the upper half is represented as scouring across 
the country. He knew that true waves were not 
emitted till beyond a quarter-wave length from the 
source. He knew how they were polarised, and how 
their intensity differed in the equatorial and polar 
directions, and how it varied with what may be called 
latitude. In fact he rapidly came to know all about 
these waves. As to us, we knew not which to admire 
most — his experimental skill when working with a 
tiresome and irritating mode of detection ; or his mathe- 
matical thoroughness in ascertaining the laws of their 
propagation. A synopsis of his equations will be found 
clearly cited in Preston’s “‘ Theory of Light,” as well 
as in other books. I translated some of his papers into 
Nature. Never was there the smallest iota of jealousy 
between us, or anything but cordial and frank apprecia- 
tion. Maxwell and Hertz are the essential founders of 
the whole system of wireless. That is to say, they 
constructed the foundations solidly and well. Of the 
super-structure—splendid as it is now—we are as yet 
far from seeing the completion. 
In March 1889 I lectured to the Royal Institution 
on “ The Oscillatory Discharge of a Leyden-jar,” and 
incidentally exhibited many of the effects of waves, 
both on wires and in free space, with overflow and 
recoil effects. But there was nothing akin to signalling 
exhibited in this lecture, as there was in the subsequent 
lecture in 1894. 
Nevertheless, Sir William Crookes, on the strength 
of these experiments—which he mentions—wrote a 
brilliant article in the Fortnightly Review for February 
1892 (vol. 51, p. 173) in which he foreshadows actual 
telegraphic accomplishment by that means, and in- 
dicates also the possibility of tuning or selective 
telegraphy, which was not actually born till 1897. 
He is evidently impressed with the experiments both 
of Hertz and of myself, and he quotes from my Phil. 
Mag. paper of August 1888 in confirmation and illus- 
tration of his prevision. For he says—after speaking 
of choosing wave-length with which to signal to specific 
people—‘ This is no dream of a visionary philosopher. 
All the requisites needed to bring it within the grasp 
of daily life are well within the possibility of discovery, 
and are so reasonably and clearly in the path of re- 
searches now being actually prosecuted in every capital 
of Europe, that we may any day expect to hear they 
have emerged from the realm of speculation into that 
of sober fact.” Then he goes on—evidently refer- 
ring to the experiments of D. E. Hughes, at which 
