Moseley and X-ray spectroscopy part 2

 The apparatus consisted of a rack of pure samples of elements inside a vacuum tube above.

 When that element was in the centre of the tube, it came under a cathode that fired a beam of electrons down onto it, shown above.

To avoid having to break the vacuum every time a new element was tested, there was an ingenious pulley system where turning a knob at the top turned a cotton reel which moved the line to which the rack of elements was attached.

The beam of X-rays from the sample then went into this chamber where it hit a prism made of a salt. The beam was then deflected round the chamber and the results photographed at different angles recorded on a scale inside.