salt solutions. For this purpose I needed the assistance of a clever
glass-blower. A Herr Mueller was recommended to me by the people of the
Physical Institute. I paid frequent visits to him, not only because I
liked to watch his wonderful skill in glass-blowing, but also because
he knew and entertained me often with the history of a remarkable
physical research which had been carried out by Doctor Goldstein, a
Berlin physicist, under the auspices of the German Academy of Sciences,
Herr Mueller, the glass-blowing artist, assisting.
The motion of electricity through rarefied gases was first extensively
studied in Germany in the fifties and sixties by several investigators.
Hittorf was one of them, and I mention him here for reasons given
later. The English physicists took up the subject a little later,
and among them Crookes did the most distinguished work. His tubes
with a very high vacuum gave brilliant cathode rays, first discovered
by Hittorf, which produced among other things the well-known
phosphorescence in vacuum tubes made of uranium glass. In spite of the
surpassing beauty of the electrical phenomena in vacuum tubes revealed
by Crookes’s experiments, no final and definite conclusions could be
drawn from them toward the end of the seventies. But he was undoubtedly
the first who correctly inferred that the cathode rays were small
electrified particles moving with very high velocity. This inference
proved to be of very great importance. In 1893 Lord Kelvin said: “If
the first step toward understanding the relations between ether and
ponderable matter is to be made, it seems to me that the most hopeful
foundation for it is knowledge derived from experiment on electricity
in high vacuum.” This was the very opinion which Helmholtz had
formulated fifteen years earlier, and he persuaded the German Academy
of Sciences to make a special grant for a thorough experimental review
of the whole field of research relating to electrical motions in high
vacua. Doctor Goldstein was selected to carry out this work. Mueller
was his glass-blower. The most important result of this work was the
discovery of the so-called _Canal Rays_, that is, motion of positive
electricity in the direction opposite to the motion of negative
electricity, the latter being the cause of the _cathode rays_. To get
that result Mueller had to make innumerable vacuum tubes of all sorts
of shapes. He told me that if all these tubes could be resurrected they
would fill the house in which his shop was located. “But the grand
result was worth all the trouble, and I am proud that I did all the
glass-blowing,” said Mueller, with a triumphant light in his eyes,
and his beaming countenance testified that he felt what he said. He
was an artisan who loved his craft; and, judging from his remarkable
knowledge of all the vacuum-tube researches which had been conducted
up to the time of his co-operation with Doctor Goldstein, I inferred
that he was a unique combination of the science and the art involved in
the job which he was doing for Doctor Goldstein. Mueller was the first
to arouse my interest in the results of vacuum-tube researches, and I
always considered him one of my distinguished teachers in Berlin. New
knowledge is not confined to the lecture-rooms of a great university;
it can often be found in most humble shops, treasured by humble people
who are quite unconscious that they are the guardians of a precious
treasure. Mueller was one of these humble guardians.
The importance of Goldstein’s work was due principally to the fact
that it brought into the field three other German physicists of
great acumen. The first one was Hertz. Several years after he had
completed his splendid experimental verification of the Faraday-Maxwell
electromagnetic theory, he showed that the cathode rays penetrated
easily through thin films of metal, like gold and aluminum foil,
although these films were perfectly opaque to ordinary light. It was
a novel and most important contribution to our knowledge of cathode
rays, and would have been followed up by more additional knowledge
if Hertz had not died on January 1, 1894, at the age of thirty-six.
Helmholtz died several months later. Science never suffered a greater
loss in so short an interval of time. Helmholtz met with an accident
on the ship on his return trip from the United States in 1893. He
never completely recovered, although he lectured at the University of
Berlin until a few days before his sudden death in the mid-summer of
1894. Autopsy revealed that one side of his brain was and had been in a
pathological state for a long time, but nobody had ever observed that
his intellectual power had shown any signs of decay. It is a pity that
he did not live another two years; he would have seen what he told me
during his visit here he longed to see, and that is an electrified body
moving at a very high velocity suddenly reversing its motion. That, he
thought, might furnish a direct experimental test of the mobility of
ether. The discovery described below furnished such a body.
Hertz’s work was continued and greatly extended by Professor Lenard
of the University of Kiel. He would have undoubtedly reached the
final goal if Roentgen had not announced, in December, 1895, that he,
experimenting with Lenard vacuum tubes, had discovered the X-rays.
This discovery marked the last step in the survey which Goldstein,
under the initiative of Helmholtz, had undertaken some fifteen years
before Roentgen had entered the field of electrical discharges in
high vacua. It was a great triumph for German science. The science of
electrical discharges in rarefied gases was started in Germany and in
less than forty years it had reached there its highest point. It is a
science which may justly be said to have been “made in Germany,” just
as the science of radiation. It started a new and most remarkable era
in physical sciences by extending the meaning of the Faraday-Maxwell
electromagnetic theory.
[Illustration: SIR J. J. THOMSON (1856----)]
No other discovery within my lifetime had ever aroused the interest
of the world as did the discovery of the X-rays. Every physicist
dropped his own research problems and rushed headlong into the
research of the X-rays. The physicists of the United States had paid
only small attention to vacuum-tube discharges. To the best of my
knowledge and belief I was at that time the only physicist here who
had had any laboratory experience with vacuum-tube research, and I
got it by overtime work in the electrical-engineering laboratory of
Columbia College. I undertook it because my intercourse with Mueller,
the glass-blower of Berlin, directed my attention to this field
of research, and particularly because I did not see that with the
equipment of that laboratory I could do anything else. I decided, as
mentioned above, to leave the field to Professor J. J. Thomson, of
Cambridge, and to watch his work. When, therefore, Roentgen’s discovery
was first announced I was, it seems, better prepared than anybody else
in this country to repeat his experiments and succeeded, therefore,
sooner than anybody else on this side of the Atlantic. I obtained the
first X-ray photograph in America on January 2, 1896, two weeks after
the discovery was announced in Germany.
[Illustration: WILHELM KONRAD RŒNTGEN (1845-1923)]
Many interesting stories have been told about the rush to the West
during the gold-fever period, caused by the discovery of gold in the
far West. The rush into X-ray experimentation was very similar, and
I also caught the fever badly. Newspaper reporters and physicians
heard of it, and I had to lock myself up in my laboratory, which
was in the cellar of President Low’s official residence at Columbia
College, in order to protect myself from continuous interruptions. The
physicians brought all kinds of cripples for the purpose of having
their bones photographed or examined by means of the fluorescent
screen. The famous surgeon, the late Doctor Bull of New York, sent
me a patient with nearly a hundred small shot in his left hand. His
name was Prescott Hall Butler, a well-known lawyer of New York, who
had met with an accident and received in his hand the full charge of
a shotgun. He was in agony; he and I had mutual friends who begged me
to make an X-ray photograph of his hand and thus enable Doctor Bull
to locate the numerous shot and extract them. The first attempts were
unsuccessful, because the patient was too weak and too nervous to stand
a photographic exposure of nearly an hour. My good friend, Thomas
Edison, had sent me several most excellent fluorescent screens, and by
their fluorescence I could see the numerous little shot and so could
my patient. The combination of the screen and the eyes was evidently
much more sensitive than the photographic plate. I decided to try a
combination of Edison’s fluorescent screen and the photographic plate.
The fluorescent screen was placed on the photographic plate and the
patient’s hand was placed upon the screen. The X-rays acted upon the
screen first and the screen by its fluorescent light acted upon the
plate. The combination succeeded, even better than I had expected. A
beautiful photograph was obtained with an exposure of a few seconds.
The photographic plate showed the numerous shot as if they had been
drawn with pen and ink. Doctor Bull operated and extracted every one of
them in the course of a short and easy surgical operation. Prescott
Hall Butler was well again. That was the first X-ray picture obtained
by that process during the first part of February, 1896, and it was
also the first surgical operation performed in America under the
guidance of an X-ray picture. This process of shortening the time of
exposure is now universally used, but nobody gives me any credit for
the discovery, although I described it in the journal _Electricity_, of
February 12, 1896, before anybody else had even thought of it. Prescott
Hall Butler was much more appreciative and he actually proposed, when
other offers to reward me for my efforts were refused, to establish a
fellowship for me at the Century Club, the fellowship to entitle me to
two toddies daily for the rest of my life. This offer also was refused.
On March 2, 1896, the late Professor Arthur Gordon Webster, of Clark
University, Worcester, Massachusetts, addressed a letter to the
_Worcester Gazette_, from which I quote:
Sunday morning I went with Professor Pupin to his laboratory to
try the effect of a fluorescent screen in front of the plate. I
placed my hand under the bulb and in five minutes the current
was stopped.... The result was the best plate that I had yet
seen.... One who has tried the experiments and seen how long it
takes to obtain a good result can judge of an improvement. I think
that Doctor Pupin should enjoy the credit of having actually ...
shortened the time of exposure ten and twenty times.
A description of the improvement, which I published in final form in
_Electricity_, of April 15, 1896, ends with the following sentence:
My only object in working on the improvement of the Roentgen
ray photography was for the purpose of widening its scope of
application to surgical diagnosis. I think that I have succeeded
completely and I wish full credit for the work done.
My friends suggested that I apply for a patent on the procedure and
enforce recognition that way, but I was having one expensive experience
in the patent office with my electrical resonators and did not care to
add another.
The question of reflection and refraction of the X-rays had to
be answered, and several strange claims were brought forward by
investigators. My investigations of this matter, aided by Thomas
Edison’s most efficient fluorescent screen, resulted in a discovery,
which, in a communication to the New York Academy of Sciences,
on April 6, 1896, I summed up as follows: “_Every substance when
subjected to the action of X-rays becomes a radiator of these rays_.”
The communication was published in several scientific journals, like
_Science_ and _Electricity_, and no statement can claim the discovery
of the now well-known secondary X-ray radiation more clearly than the
one given above. But of this matter I shall speak a little later.
Looking up some data lately I found that I had finished writing out
these communications relating to my X-ray research on April 14, 1896.
I also found a reprint of an address delivered before the New York
Academy of Sciences in April, 1895, and published in _Science_ of
December 28, 1895, at the very time when the X-ray fever broke out.
It was entitled: “Tendencies of Modern Electrical Research.” But the
X-ray fever prevented me from reading it when it was published. I saw
it three months later, but never again since that time, and I had
forgotten that I had ever composed it. I find now that the picture
which I had drawn then of the growth of the electromagnetic theory is
in every detail the same as that which I have given in this narrative.
Both of them are due to the lasting impressions received in Cambridge
and in Berlin. Evidently these impressions are just as strong to-day as
they were twenty-eight years ago, proving that the tablets of memory
have a mysterious process of preserving their records. I remember
that on April 14, 1896, I did not go to the laboratory, but stayed
at home and reflected, and read my address mentioned above. I took
an inventory of what I had done during my six years’ activity at
Columbia and I closed the books satisfied with the results. My wife,
who had helped me, writing out my reports, lectures, and scientific
communications, and who knew and watched every bit of the work which
I was doing, also was satisfied, and congratulated me. My colleague
Crocker, I knew, was satisfied, and so were all my scientific friends,
and that was a source of much satisfaction. But nothing makes one as
happy as his own honest belief that he has done his best.
XI
THE RISE OF IDEALISM IN AMERICAN SCIENCE
I must make a digression now, to arrange suitable contacts between the
preceding parts of my narrative and its concluding chapters. The main
object of my narrative has been to describe the rise of idealism in
American science, and particularly in physical sciences and the related
industries. I witnessed this gradual development; everything I have
written so far is an attempt to qualify as a witness whose testimony
has competence and weight. But there are many other American scientists
whose opinions in this matter have more competence and weight than
my opinion has. Why, then, should a scientist who started his career
as a Serbian immigrant speak of the idealism in American science,
when there are so many native-born American scientists who know more
about this subject than I do? Those who have read my narrative so far
may answer this question. I shall only point out now that there are
certain psychological elements in this question which justify me in the
belief that occasionally an immigrant can see things which escape the
attention of the native. Seeing is believing; let him speak who has the
faith, provided he has a message to deliver.
* * * * *
A foreign-born citizen of the United States has many occasions to
sing praises of the virtues of this country which the native-born
citizen has not. Such occasions arise whenever the foreign-born citizen
revisits his native land and hears opinions about America which are
based upon European prejudice born of ignorance. On these occasions he
can, if the spirit moves him, say many things with much more grace than
a native American could. The spirit will move him if his naturalization
means that he knows America’s traditions and embraces their precepts
with sincere enthusiasm. Statements which, coming from a native
American, might sound as boasts and bragging, may and often do sound
different when they are made by a naturalized American citizen. I have
had quite a number of experiences of this kind; one of them deserves
mention here.
Four years ago, while visiting my native land, I was invited to attend
a festive public meeting in a town not far from my native village. It
was the town of Panchevo, where in my boyhood days I went to school,
and where from my Slovenian teacher, Kos, I had heard for the first
time of Benjamin Franklin and of his kite. The earliest parts of this
narrative show that many memories of my boyhood days had nourished
in my heart an affectionate regard for this historic town. Panchevo
reciprocated, and hence the invitation. There was another reason. In
March of 1919, the chairman of the Yugoslav delegation at the Paris
peace conference invited me to go to Paris, expecting that with my
knowledge of the English language and of the Anglo-Saxon mentality I
could probably assist the delegation in its work. I spent seven weeks
in Paris. The result, I was assured by Premier Pashitch of Serbia,
was very satisfactory; and he invited me to go to Belgrade as guest
of the government, for the purpose of studying the condition of the
war orphans in Serbia. This study resulted in the organization of the
Serbian Child Welfare Association of America, whose splendid work
is known and appreciated in every part of the Serbian nation. When
Panchevo heard that I was in Belgrade it sent me the invitation.
The literary society of Panchevo, called the Academy, had arranged a
gala public session, and the occasion was the “Wilson Day,” which
the town was celebrating. The orator of the day was a young Slovene,
a learned lawyer and man of letters. The subject of his oration was:
“President Wilson and his fourteen points.” He wound up his splendid
eulogy of President Wilson by exclaiming: “_President Wilson is an
oasis of idealism in the endless desert of materialism_.” The image
of my old friend Bilharz, the hermit of Cortlandt Street, suddenly
appeared before me, and his favorite phrase “American materialism” rang
violently in my ears. I was afraid that the United States of America
would be understood to be a part of the endless desert mentioned by the
speaker, and the possibility of such an inference I did not like. A
most enthusiastic and long-continued applause greeted this oratorical
climax, and before the applause was over the chairman, who was the
mayor of the town, approached me and asked whether I should like to
address a few words to the great assembly of the intellectuals of the
town. “I not only like to do it,” said I, “but I insist upon it.” The
chairman looked pleased, because he could not help observing that the
orator’s concluding figure of speech had stirred me up considerably,
and that my response to it might add a few lively notes to the rather
monotonous programme of the Academy session.
I repeat here some of the sentiments which I expressed on that occasion:
President Wilson is an idealist, and his idealism commands my
deepest respect and admiration. I deny, however, that he represents
an “oasis of idealism in an endless desert of materialism,” that
is, if the United States of America are understood to be a part
of this endless desert. I am sure that in this town, liberated
only a few months ago from the Austrian yoke, the expression
“materialism” cannot refer to the United States of America. Two
million American soldiers were fighting on the Western front when,
a few months ago, the armistice was signed; several million more
were waiting in America for their turn to join the ranks of the
allied armies in France. American industries and American savings
made a supreme effort to brace up the allied cause, and the war
was won. Go to Paris now and watch the proceedings at the peace
conference, as I was doing during the last seven weeks, and you
will find that America asks for no territories, for no mandates,
and for no onerous compensations. It is the only great power there
which preaches moderation, and demands unreservedly full justice
for the little nations. Yugoslav Dalmatia, Istria, Goricia, and
Fiume had been, in a period of stress, bartered away by some of our
allies; America is to-day the only fearless champion of your claims
to these Yugoslav lands. American men and women hastened to every
front, and there, amid many perils and discomforts, they nursed the
sick and the wounded. They fed the hungry and clothed the naked and
the destitute. This they did even before America had entered the
world war. Need I remind you that it was an American mission which,
in 1915, saved Serbia from the destructive ravages of typhus,
and that several Americans, victims of these very ravages, are
now buried in Serbia’s soil? To-day you will find Americans even
in the countries of our former enemies, in Germany, Austria, and
Hungary, doing the work of mercy and of charity. The name of Hoover
is just as well known and beloved in Vienna and Budapest as it is
in Belgium. A country of materialism cannot display that spirit
which America has displayed during this war. Let the idealism of
President Wilson remind you of American idealism.
The phrase “American materialism” is an invention of ill-informed
Europe; but the European who has lived in the United States, and
has had the good fortune to catch the spirit of America, revolts
whenever he hears the untutored European mind utter that phrase.
Read the history of the United States from its earliest beginnings,
when the Pilgrim fathers landed at Plymouth Rock, three hundred
years ago, and you will find that idealism runs through it from
beginning to end. The Pilgrim fathers themselves were idealists,
who undertook the perilous voyage “for the glory of God and the
advancement of the Christian faith.”
A hundred and fifty years later the Continental Congress of
the colonies issued, at Philadelphia, the “Declaration of
Colonial Rights,” and this declaration, as well as the documents
accompanying it and addressed to the people of the United Kingdom
and of British America, breathes the spirit of lofty idealism. The
same Congress in 1775 issued another declaration, setting forth
causes which forced the American colonies to take up arms; and in
1776 it issued the Declaration of Independence, which announced
to the world the ideals for the attainment of which the colonists
were ready to sacrifice their lives. No other human documents ever
stated so clearly and so definitely the “divine right of man” as
these documents did. The men who composed these documents were
not ordinary men; they were idealists of the highest type. Read
the lives of Washington, Hamilton, Franklin, Jay, Jefferson, and
of other leaders of the American Revolutionary period, and you
will find what a wonderful power idealism has when the destiny of
a young nation hangs in the balance. But when the struggle was
over, after the victory had been won, the leader of the new nation,
immortal Washington, assumed the supreme executive office of the
land and retired from it after two terms of service with a spirit
of dignity and of humility which has no equal in human history. His
Farewell Address to the American people, advocating the practice of
idealism by the cultivation of religion, morality, patriotism, good
faith, and justice toward all nations, is an echo of the voice of
idealism which was the driving power of the American Revolution.