New-York tribune., 1901-08-26
SMALLER THAN ATOMS
PROFESSOR THOMSON TELLS HOW
MADE HIS DISCOVERY.
a POPULAR EXPLANATION OF A STARTLING sr
ENTIFIC ANNOUNCEMENT.

- A' A->' -->-'<AAiON Os' "A STARTLING SCI
ENTIFIC ANNOUNCEMENT.
II Is hard TO say which Is the more wonss-,, .
lhhhi'ey great things OF the universe. Ike STEM
distances, or the infinitely little ones Tbs .,Ia
orate structures OF diatoms. mere particles OF w.
etable dust apparently. is simply amazing - es-
who first examines them with a microseonA ~, -ne
influence upon human health and happiness =, h s
terra. duly considered. is even more fn,nra c-
bul perhaps the imagination is most strongly t,x,
when 1t tackles atoms. Of the constituent uartirr
OF which. chemists tell us matter is made up r..
are so inconeeivably small, as described by Kslvr
that the average mind cannot form any prouer "a
or them- The most powerful microscope one vbI.1
will readily reveal the bacillus tuberculosis vr,
not show an object containing thousand atorrs,
And yet within the last few months Professor =
Thomson. of Cambridge. England. has been irwin.
TO persuade the scientific world that there are h,,
Of matter ineomparably smaller than these srs
divisions OF matter
The scientific world. while yet fully convince,
and indeed. so staggered by the announcenan,
that 1T cannot yet form definite conclusion ba
listened attentively Not only is the subject one ot
immense importance in chemistry and physics In,
this new phase of it is presented by an experiences
and cautious Investigator. There Is TO-DAY No
higher authority than this Cambridge scholar a,
the behavior of rarefed gases under the Insr
euce of electricity-not even Sir William Crooks.
after whom the Crookes tube is named
Most of Professor Thomson's outgivings concar,.
ing his supposed discovery have been couches \,
technical language, ineligible only to the few
But his article in the September "Harper's" deal,
with it in much more popular fashion. and give,
an excellent idea Of the manner IN which Ia
reached his startling conclusion.
Into the ends OF an ordinary vacuum tube ara
sealed the terminal wires of a peculiar kind Of
electric circuit The current leaps across the gan
within, from the positive wire anode to tbs
negative wire. or cathode. In doing ii produces
two phenomena. luminous glow OF the gas which
tends 70 concentrate around the cathode and
phosphorescence of the glass at that end Of ths
tube. For long time it supposed that this
action stopped there. But Lenard and Rontgsp
found that there also invisible radiancs
which operated beyond the walls OF the tube. Sub
sequent investigation showed that this while pro-
duced by the rays within, is different therefrom
To the new phenomenon Rontgen gave the lams
~ rays"
Long before this interesting development there
was lively discussion concerning the exact nature
OF the agent which gave rise to all these observed
effects Experiments soon proved that il emanated
GiA IrGna tne catn9de, ogt the vital question was
projected from the terminal or resemhled ordinary
c1ne 70 ing fnTe 8ia S long age ampIoxs5 m
phrase radiant matter 10 describe it, Thomson.
sides of the case in "Harper's' with considerable
fairness. And it was while engaged In studying
had found something very much smaller than
atom To differentiate one from the other he calls
Perhaps the greatest logical objection to the
notion that the cathode rays solid particles is
that they will penetrate solid objects like metal,
glass and wood The world has long been aceus-
toned 70 seeing one kind OF ether waves-ight-go
through what called transparent substances.
And Hertz showed that another kind-electro-mag-
nettc vihrationS-would go through a stone wall
But IL hard see how bombardng particles
could go through even The thinnest Of glass tubes.
The trouble disappears, however, the instant that
one cOneeiveS OF the atoms composing the sass
or other solid as being hundred or a thousand
times as large as the corpuSCle. In that the
interstices between them would be so large that
the smaller particles would flow like water through
a sieve.
As long ago as 1896 Perrin discovered that the
cathode carried with them a OF
tive electricity. 1t seemed a necessary conclusion
from this fact that the electricity borne along
on the surface OF solid PARTICLES And In 1887 Thom-
son undertook to ccn1puC-. from previously esab-
HShed principles. the size of the carrier the in
tensty OF the charge and the velocity at which the
particle moved He thus convinced that the
atom of hydrogen. the smallest object hitherto
known 10 the chemist, was fully a thousand times
| bigger than his cOrpuScle OF radiant matter and
that 10 travelled with velocity about Onethird as
great that OF light
In "Harper's'' Professor Thomson does not de-
| expert could understand them. perhaps. But hs
gives number of incidental discoveries which he
| made in the course OF his researches Whatever
| the gas in the tube the metal OF which the
| mains the same. The particles of gas which carry
positive charges IN a vacuum tube have also been
measured, but they always correspond IN size 70
the atom. mOlecule 1t has been found, too that
| a white hot wire in a vacuum, and il seems PROB
able that the sun must give out such emana
ton, too. Already scientific have been puzzled
by the strange radiation from uranium salts and
corpuscular theory supplies the necessary expana
ton.