first x-ray photograph

1895 - Wilhelm Conrad Röntgen of Germany experiments with black paper wrapped around a Geisler Tube & notices a nearby powdered substance fluorescing. Curious about what manner of radiation was passing through the black paper, he first placed a board & then a book of 1,000 pages between the tube &
the powder, but that only dimmed its glow.

He later began experimenting with the rays & a fluorescent screen, accidentally passing his hand between the two and seeing a
silhouette of his bones on the screen.

Within about a month he took the first x-ray photo, which was of his wife's hand.
Rautgen received the 1st Nobel prize for Science, gave the prize money to the University of Würzburg, refused to patent his invention, and
taught physics into his 70's.

The First X-Ray at The Scientist | Discovery of X-Rays at NDE-ed.org

Röntgen at The Roentgen-Memorial | Röntgen at Würzburg University

Röntgen and the Discovery of X-rays at The National Center for Biotechnology Information




A "Diffraction Grating" was need to study these new "Rautgen (Röntgen) Rays", later called X-Rays, because they were too small for ordinary methods of measurement, and it was presumed natural crystals had an extremely architectural structure that would assist in the separation of the x-rays so they could be further studied. The assumptions were proven correct when x-ray photography revealed the ordered, trellised formation of the molecules in crystals. This allowed the x-rays to be "diffracted", since the crystals were small enough to alter the path of the x-rays and "sort" them by wavelength.

constructive interference

Diffraction Grating at Southern Methodist University | Diffraction Grating at Georgia State University

Diffraction Gratings at Richardson Gratings | Diffraction Grating at Boundless


Braking of the Electron

The "braking" of a cathode-ray electron, or its sudden deceleration upon striking mass, causes heat by transferring its kinetic energy to
electromagnetic energy.

A faster electron will also produce light.

Even faster electrons can interfere with electron shells
close to the nucleus, producing an x-ray.

outer shell electrons hurled out of orbit -
Description of ionization:

Prof. Robert Reiland, ret., Indiana University of Pennsylvania

X-Ray visually depicted

Contrast the loss of electrons at outer orbit with those at inner orbit - this produces a greater change to the structure of the atom
(analogy of a brick wall losing bricks at the top versus at the bottom).

Electrons from outer level forcefully replace those lost at inner orbit, releasing a large discharge of energy.
(about one in 1,000 fast-moving electrons will reach to this inner level & actually produce an x-ray).

The Bohr Atom at chem1.com | Electron Configuration and Valence Electrons at Spark Notes

X Rays at Doane University


picture of Henry Mosely
Moseley at Oxford, 1910

1912 - as assistant at the University of Manchester,
Henry Moseley
studies atomic structure with the x-rays by producing diffraction patterns of various elements.

By using an x-ray tube, and also by substituting the prism with a crystal,
he was able to produce an X-ray Spectrograph.

X-rays were produced from differing elements which were placed as anticathodes in the path of the electron-emitting,
negatively charged cathode.


photograph of early Spectromter
Bragg's X-Ray Spectrometer, 1915

Sir William Henry Bragg at The Royal Institution

The X-ray Spectrometer at University of Leeds

X-ray Spectrometer -
a spectrometer using x-rays to activate the inner electrons of an atom in order to separate and identify the chemical constituents of a substance and their concentrations.

- Dictionary.com


Discovery of the smallest electric charge - definition of the electric charge as energy, not the electron itself:

Electricity is not the flow of electrons, instead it's the electrons and protons themselves.
- amasci.com/miscon/whatdef.html