Early History of X Rays
by ALEXI ASSMUS
10 SUMMER 1995
The discovery of X rays
in 1895 was the
beginning of a
revolutionary change
in our understanding
of the physical world.
I
N THE WINTER of the year of his fiftieth birthday, and the year
following his appointment to the leadership of the University
of Würzburg, Rector Wilhelm Conrad Roentgen noticed a barium
platinocyanide screen fluorescing in his laboratory as he
generated cathode rays in a Crookes tube some distance away.
Leaving aside for a time his duties to the university and to his
students, Rector Roentgen spent the next six weeks in his laboratory, working alone, and sharing nothing with his colleagues.
BEAM LINE 11
Three days before Christmas he
brought his wife into his laboratory, and they emerged with a photograph of the bones in her hand and of
the ring on her finger. The Würzburg
Physico-Medical Society was the first
to hear of the new rays that could
penetrate the body and photograph
its bones. Roentgen delivered the
news on the 28th of December 1895.
Emil Warburg relayed it to the Berlin
Physical Society on the 4th of January. The next day the Wiener Press
carried the news, and the day following word of Roentgen’s discovery
began to spread by telegraph around
the world.
On the 13th of January, Roentgen
presented himself to the Kaiser and
was awarded the Prussian Order of
the Crown, Second Class. And on the
16th of January the The New-York
Times announced the discovery as
a new form of photography, which
revealed hidden solids, penetrated
wood, paper, and flesh, and exposed
the bones of the human frame. “Men
of science in this city are awaiting
with the utmost impatience the
arrival of English technical journals
which will give them the full particulars of Professor Roentgen’s discovery of a method of photographing
opaque bodies,” The New-York
Times began, and it concluded by predicting the “transformation of modern surgery by enabling the surgeon
to detect the presence of foreign
bodies.” (Jan. 16, 1896, p. 9)
The public was enthralled by this
new form of photography and curious to know the nature of the new
rays. Physicians put it to immediate
use. Physicists sat up and took notice. The discovery of X rays was the
first in a series of three discoveries
that jolted the finde-siècle discipline out of its
mood of finality,
of closing down
the books with
ever more precise
measurements, of
losing itself in debates over statistical
mechanics, or of trying to ground all
physical phenomena in
mathematically precise
fluctuations of the ether.
All three discoveries, X rays,
uranium rays, and the electron, followed from one of the
major experimental traditions in the
second half of the nineteenth
century, the study of the discharge
of electricity in gases. All three
contributed to a profound transformation of physics. In the 20th century, the discipline has been grounded in the study of elementary
particles.
As with the invention of incandescent light
bulbs, the study
of electrical discharge through
gases was made
possible by the
development of
improved vacuum technology
in the 1850s. Early on, English
scientists were
investigating the
patterns of light
and dark that appeared in sealed
lead-glass tubes.
The patterns in
W
https://www.slac.stanford.edu/pubs/beamline/25/2/25-2-assmus.pdf
No comments:
Post a Comment