328 
NATURE 
[MaRcH 10, 1923 
The Origin or Basis of Wireless Communication.’ 
By Sir Ottver Lopes, F.R.S. 
EOBEPUBY Technical College has done splendid 
work throughout its short history. It fills a 
distinct niche, it supplies a felt want in the education 
of the Central metropolis, and I hope that any idea of 
closing it has now subsided. It has had, moreover, 
a brilliant array of teachers, men who appeared 
specially adapted to serve the needs of its special kind 
of students. I will here only mention three con- 
temporaries who worked together after 1885, when 
the initial start had been made, and the early 
traditions settled, by Ayrton and Perry. Silvanus 
Thompson became principal in 1885, and had as his 
colleagues John Perry and Raphael Meldola. John 
Perry was remarkable as a teacher, and did his best to 
cultivate a wider interest in the rather narrow technic- 
ally trained students who came under his paternal 
supervision, encouraging them to read novels, to take 
an interest in literature, and—even in mathematics— 
to take a broader outlook than most teachers thought 
it worth while to cultivate. As for Silvanus Thompson, 
the breadth of his outlook and width of his interests 
are almost proverbial. He represented a rare com- 
bination of scientific aptitude and high artistic faculty, 
together with a fondness for literary study among 
archives, and he became in the eyes of all his con- 
temporaries—including Lord Kelvin and Lord Rayleigh 
—a recognised historian of science. He had a keen love 
of the past and of discoveries in their nascent stages. 
Old documents and records were of real interest to him : 
and he used to do his best to dig out of obscurity some 
of the pioneers and early workers towards developments 
which afterwards became famous. 
Early pioneering work is too often overlooked and 
forgotten in the rush of a brilliant new generation, and 
amid the interest of fresh and surprising developments. 
The early stages of any discovery have, however, an 
interest and fascination of their own; and teachers 
would do well to immerse themselves in the atmosphere 
of those earlier times, in order to realise more clearly 
the difficulties which had to be overcome, and by what 
steps the new knowledge had to be dovetailed in with 
the old. Moreover, for beginners, the nascent stages 
of a discovery are sometimes more easily assimilated 
than the finished product. Beginners need not, indeed, 
be led through all the controversies which naturally 
accompany the introduction of anything new; but 
some familiarity with those controversies and dis- 
cussions on the part of the teacher is desirable, if he 
is to apprehend the students’ probable difficulties. 
For though he does not himself feel them now, the 
human race did feel them at the new fact’s first 
introduction ; and the individual is liable to recapitu- 
late, or repeat quickly, the experience of the race. 
A large number of people now interested in the most 
modern developments of wireless have but little idea— 
perhaps none at all—of the early work, in apparently 
diverse directions, which preceded and made such 
developments possible. Even those who are high 
authorities in wireless telegraphy, and know nearly all 
that can be known about it—like the distinguished 
_’ From the first Silvanus P. Thompson memorial lecture delivered at 
Finsbury Technical College on February 1. 
NO. 2784, VOL. 111] 

dean of this college, Dr. Eccles—can scarcely know 
the early stages quite as well as Silvanus Thompson 
and I knew them; no one, ifdeed, can afterwards 
feel in touch with the history so closely as those who 
have lived through the period covered by it. Only 
those who have survived the puzzled and preliminary 
stages of a discovery can appreciate fully the contrast 
with subsequent enlightenment. It may suffice to say 
that the term “inductance” or “ self-induction,” 
which we now use so glibly, did not at first exist ; and 
that so late as 1888 Sir William Preece still spoke 
of it as “a bug-a-boo”’: whereas it is the absolute 
essential to tuning, and even to electric oscillation. 
Faraday was the first to direct attention to it, under 
the name “electrotonic state ;’’ and he treated it ex- 
perimentally with his usual skill. Lord Kelvin, who 
first introduced it as a mathematical coefficient, without 
any explanation, called it “ electrodynamic capacity.” 
The name self-induction was given to it by Maxwell, 
though it was long before it was understood or utilised, 
and the name “ inductance” is a nomenclature of 
Heaviside.” 
I wish in this lecture to say practically nothing about 
anything to do with wireless later than 1896. What I 
have to deal with is the early pioneering work apart 
from practical developments. Let me here say at once, 
to avoid misunderstanding, that without the energy, 
ability, and enterprise of Signor Marconi, what is now 
called wireless would not have been established com- 
mercially, would not have covered the earth with its 
radio stations, and would not have taken the hold it 
has upon the public imagination. Before 1896 the 
public knew nothing of its possibilities: and for some 
time after 1896, in spite of the eloquence of Sir William 
Preece and the demonstrations by Signor Marconi, the 
public thought it mysterious and almost incredible ; 
and still knew nothing about the early stages. Indeed, 
I scarcely suppose that Signor Marconi himself really 
knew very much about them. He had plenty to do 
with the present ; he felt that the future was in his 
hands ; and he could afford to overlook the past. 
It may be doubted whether the younger generation, 
who are so enthusiastically utilismg, and perhaps 
improving, the latest inventions, will care much about 
the past either. Incidentally, however, I want to say 
two things to those who are occupied with the subject 
to-day. First, do not hesitate to speak and think of 
the ether of space, as the continuous reality which 
connects us all up, and which welds not only us but all 
the planets into a coherent system. Do not be misled 
by any misapprehensions of the theory of Relativity 
into supposing that that theory dispenses with the ether, 
merely because it succeeds in ignoring it. You can 
ignore a thing without putting it out of existence : 
and the leaders in that theory are well aware. that 
for anything like a physical explanation of light or 
electricity or magnetism or cohesion or gravitation, the 
ether is indispensable. The ether has all these functions, 
and many more. We are utilising it every day of our 
? Silvanus Thompson wrote a pamphlet on the early history of wireless, in 
connexion with a successful application before Lord Parker for the extension 
of my fundamental tuning patent of 1897. This pamphlet has never been 
published, but it ought to be. I had not time to quote from it. 
