CATHODE RAYS

I am pleased to fulfil my obligation as a Nobel Prize winner to talk to you here on cathode rays. I assume that you would prefer me to tell you what others could not tell you. I shall describe to you the development of the subject which also embraces recent theories concerning electricity and matter as it has appeared to me, on the basis of my own experience.* This will give me a welcome opportunity of showing on the one hand how my work has depended on that of others, and on the other how in one or two points subsequent, or more or less contemporary, work by other investigators is related to mine. Thus using the simile which you, my esteemed colleagues of the Academy of Sciences, have used at the head of your member’s diploma** I shall now speak not only of the fruits but also of the trees which have borne them, and of those who planted these trees. This approach is the more suitable in my case, as I have by no means always been numbered among those who pluck the fruit; I have been repeatedly only one of those who planted or cared for the trees, or who helped to do this. In the time at my disposal I can deal at length with only a few aspects of my work in the field under discussion. The start takes me back 26 years to Crookes. I had read his lecture on "radiating matter" (5)*** his term for cathode rays**** and was greatly impressed by it. You are all acquainted with the tests he made. Here Fig. 1 is one as a reminder: the glass tubes with highly rarefied air; the negatively charged plate or cathode (a) on which the rays are produced; a cross (b) in the path of the rays, and here the shadow of the cross (d) thrown by the rays