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INTRODUCTION
vestigation which might well be taken for the work of an
experienced investigator.
BERLIN, 31st October 1878.
I have been attending lectures-Kirchhoff's-since Monday:
another course only begins on Wednesday next. Besides this I
have also started practical work; one of the prize problems for
this year falls more or less in my line, and I am going to work at
it. This was not what I intended at first, for a course of lectures
on mineralogy, which I wished to attend, clashed with it; but I
have now decided to let these stand over until the next semester.
I have already discussed the matter with Professor Helmholtz,
who was good enough to put me on the track of some of the
literature.
A week later we find him already at his experiments.
6th November 1878.
Since yesterday I have been working in the laboratory. The
prize problem runs as follows: If electricity moves with inertia
in bodies, then this must, under certain circumstances, manifest
itself in the magnitude of the extra-current (i.e. of the secondary
current which is produced when an electric current starts or stops).
Experiments on the magnitude of the extra-current have to be
made such that a conclusion can be drawn from them as to inertia
of the electricity in motion. The work has to be finished by 4th
May; it was given out as early as 3rd August, and I am sorry
that I did not know of it before. I ought, however, to say that
at present I am only trying to work out the problem, and I may
not succeed in solving it satisfactorily: so I would not readily
have spoken of it as a prize research, indeed I would not have
mentioned it at all, if it were not necessary by way of explanation.
Anyhow I find it very pleasant to be able to attack such an in-
vestigation. So yesterday I informed Professor Helmholtz that
I had considered the matter and would like to start work. He
then took me to the demonstrators and very kindly remained some
twenty minutes longer, talking with me about it, as to how I had
better begin and what instruments I should require. So yesterday
and to-day I have begun to make my arrangements. I have a
room all to myself as large as our morning room, but nearly
twice as high. I can come and go as I like, and you will easily
see that I have room enough. Everything else is capitally
arranged. . Nothing could be more convenient, and I can only
hope now that my work will come up to its environment. Of
...
1 A large room in his parents' house.
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