New-York tribune., 1902-04-22
LORD KELVIN ON SCIENCE.
HE GIVES HIS VIEWS ABOUT VARIOUS
SUBJECTS.


CABLE COMPANIES ENGLAND AND THIS
COUNTRY BEHIND THE TINES
ON METRIC SYSTEM
Although the demands upon Lord KeIvin's
time and strength during the last few days have
been numberless. he consented yesterday to
talk for few minutes for publication on a
number of scientific subjects which have re-
Gently attracted popular attention. The en-
thusiasm with which he speaks and the prompt
of his responses to unexpected questions
afford gratifying assurance that. whatever be
the effect of years upon his physical vigor. his
mental powers have been magnifcenty pre-
served further charm is added to his con-
versation by manner that is peculiarly simple
dgnifed and winning
The Tribune has already mentioned the fact
that Lord Kelvin has great faith in the future
usefulness of wireless telegraphy He was
asked yesterday to discuss two or three special
phases Of that topic
The effect of Marconis work upon the sub
marine cable companies said he, will not. In
my opinion be hurtfuI. 1t will do good. not
harm. The agency will supplement. not re-
place. the old one. In fact. by popularizing
transoceanic teegraphy it will not fail to bene-
fit the cable companies"
will not the efficiency of wireless telegraphy
depend largely upon the number of tuned cir
cults that be operated simultaneously?
And have you any idea how many of these are
practicabe?'
1T is not possible to say yet. When several
messages are to be received at one point at the
same time each circuit must have differen,
pitch, to insure non-interference. That is 10
say. must respond to waves of one fire.
quency and another to waves of another fire.
quency But just how great difference in
frequencies will be necessary protect a circuit
from picking up the wrong message is yet to
be determined. However, the principle on which
the tuning system is based is perfectly sound"
LITTLE DIFFERENCE IN KINDS OF
WAVES
TN Marconi's earlier work his receiver
apparently acted upon solely or chiefly by ether
waves which were radiated sideways from the
vertical wire at his sending station and trans
mtted through the air. Subsequently he con-
nected the apparatus at both stations with the
earth. When the latter was used as con-
ductor he secured much better results Do you
think that waves which travel through the
earth differ essentially from those which travel
through the air?"
I'VE have much to learn about this phenom-
enon. We cannot say exactly how much, II any,
change occurs through the action of the earth
upon the waves 1 hardly think that are
justified in saying that there is any great di1-
ference in the forms of energy that take the two
routes, aerial and terrestrial"
"One of the suggestions which you said
TO have made TO increase the efficiency Of sub
marine cables related to the use OF the CON
denser.' to make the signals more distinct Is
there any resemblance between that idea ana
Professor Pupin's recent invention?
First let set you right about the con-
denser It was not my suggestion. but Crom-
well Varley's To use that instrument for the
purpose mentioned My principal contributions
to the apparatus employed in operating sub
marine cables were the mirror galvanometer.
which enabled messages to be received vtsually.
and the slphon recorder. which registered them
automatically
Between Mr.. Varleys and DR.. Pupins meth
ods there is this difference: The former placed
a single bit Of apparatus at the end of cable
while the latter introduces his at certain inter
walls along the whole length. DR.. Pupin. more
over aims primarily to improve telephony rather
than telegraphy. OF course. until his system Is
put into actual operation it Is difficult to form
any opinion concerning it
rs electricity likely to be used for traction
purposes on main lines. we'll as suburban and
urban railways?
Yes 1 feel sure of it. though it would not
he safe to say precisely how soon, l am not
confident that II IL in the immediate future.
Lord Kelvin had not closely followed the un-
traction
sen road, and not ready to pronounce on
their significance
PLEASED AT FULFILMENT OF PROPHECY
Reference was made in these columns few
davs ago to Lord Kelvin's connection with the
work of Harvesting Niagara. In many respects
a pioneer enterprise. Even before he was con-
suited concerning that project he made pre-
diction that it would be feasible TO transmit
10000 horsepower economically in the form of
n fIfn nj a
pressure of 10000 volts employed He ex-
pressed delight yesterday over the close ap-
proach to fulflment of that prophecy which
california now affords. Out near the Pacific
Coast electricity is being sent for 223 miles from
the point where 1t is generated and at about
60. 600 volts Whether further increase of press
,,re would be risky not is a question which
electrical engineers have considered very care
fully Lord Kelvin expresses confidence. how
ever in the practcability and safety OF ooo"o
volts. -,
The conversation touched on the an.
nouncement by Professor j. j. Thomson, OF
Cambridge England that he had detected the
sandth the size of hydrogen atom
rs this story credible?
who have been familiar with the electrician
theory of atoms, and who have been accuS-
toned to think of smaller bodies than atoms
'Do British physicists place nuch cohnuehce
In the accuracy of Professor Thomsons meas
urements? ,,,, t5 ,,+ tho
otatamsnt forward modestly. and not positively
The line of investigation is highly suggestive.
though it has not reached conclusive stage
..yviu this alleged discovery lead you to modify
vour faith in the notion that atoms are shaped
like SNAKE rings? x-. .,s
torv some years ago and have practically aban-
doned IL for that reason
IT is we'll known In this country that you
,,,a Ionp been a champion Of the metric sys
tenn of weights and measures Do you see any
chance of its immediate ADOPTION IN England:
fS hal m ind