This shows that the binding force between atoms in a compound is electrical. The candy cane-shaped tube bent the cathode rays in a magnetic field and showed their path on a fluorescent screen. This enabled the calculation of the Charge to Mass Ratio . Higher charge would bend the beam more, higher mass would bend the beam less. X-Rays would add or subtract electrons to the microscopic droplets.
All electrons are identical.
The electron is a basic particle of electricity. The Canal Ray Tube was built to see if there are rays from the anode. There were positive rays, but not from the anode. The Mass Spectroscope is a refined Sir JJ tube built for accurate measurements. This way we could account for a change in mass without changing which element was present.