Joseph John Thomson

“ The energy communicated to the corpuscle depends on the velocity of the particle, and unless this velocity reaches a definite value the corpuscle will not get enough energy to escape from the molecule and will thus be unable to neutralize the particle. ”

“ Hence as the minimum electrostatic deflection is the same for all the particles, we conclude that the maximum potential through which the various particles have fallen is the same for all particles. It is natural to conclude that this maximum potential is the difference of potential between the anode and cathode of the discharge tube. ”

“ The appearance of the luminosity due to the negatively charged particles shows that these, too, gain and lose negative charges in their passage down the tube.
When we reduce the pressure to the lowest value we can reach by the use of charcoal and liquid air, then with the magnet A on alone we have the spots a and b, Fig. 22. There Is no luminosity between them and no luminosity above a, while, when both magnets are on, we have merely the spots a and b’ ; b and a’ have disappeared along with the luminosity inside the rectangle. ”

“ In many cases we have velocities among the same kind of particles differing as much as to make the velocity of the slowest ones less than one fifth that of the fastest In some cases the parabolas are of fairly uniform intensity along the whole of their length. ”

“ The first condition is theoretically sufficient, but when only short arcs are available, it is often difficult, unless a very high degree of accuracy is obtained In the measurement of these lines, to tell whether the curve is or Is not a parabola. ”

“ This will tend to make the electric field overlap the magnetic on the other side, i.e. the side nearest the cathode, so that when a particle first enters the field Its deflection is mainly due to the electrostatic force and is therefore horizontal; thus a particle which gets neutralized at the early stages of Its journey through the fields will have a horizontal displacement abnormally large compared with the vertical; so that the curves produced on the photographic plate by the particles which get neutralized will have a shape something like that shown in Fig. ”