D O C U M E N T 3 0 3 A U G U S T 1 9 2 4 3 0 5
oscillation period of ca. 1 sec). However, after the sphere was magnetized, rotation
immediately set in; namely, with reference to the North Pole, when it was swinging
northward, it deviated toward the east—therefore, surely the predicted (?) effect.
But: when we then rotated the entire system by 90° so that now the oscillation went
from east to west, where the magnetization of the spheres was naturally oriented
north-south again, the rotation was not only preserved, but even became consider-
ably stronger. A repetition of this experiment in a north-south direction confirmed
this result. When we then laid a very weakly magnetized pocket knife nearby on a
table, the effect disappeared almost entirely: the sphere oscillated without rotation;
and when we moved the knife even closer, it turned around, i.e., now the sphere
turned toward the west when it was swinging toward the north—naturally, all these
series of observations were conducted such that the torsional oscillations at the start
of the pendulous swing were practically zero and gradually built up to a maximum
oscillation. So, we have nothing up to now but a presumably quite sensitive method
to detect slight inhomogeneities in the Earth’s magnetic field.—In the case of the
east-west oscillation, e.g., the sphere oscillated parallel to the not very distant wall
of the room, which in any case contains some sort of interior piping. This is one of
the difficulties I was afraid of from the start; in order to make some progress with
the actual experiment, one must first of all liberate oneself from such disturbances.
I don’t know how far this is possible; in any event, we want to go at it again after
our return to the institute. At present, Zurny [?] is on his way to Spitzbergen and I
am staying in Munich for a fortnight, and thereafter am going into the mountains
for a little while before the scientists’ convention.
You surely already know of the latest grand deed by Lenard and Stark? In a “pro-
motional book” Deutschland und Deutschheit [Germany and
Germanness],[2]
which I unfortunately only know of in excerpt, they write among other things: that
spirit of total clarity, of honesty etc. “But we already recognized and revered this—
to us (the natural scientists) exemplary—spirit early on, in the great researchers of
the past as well: in Galilei, Newton, Kepler, Faraday. We admire and revere it in the
same way also in Hitler, Ludendorff, Pöhner, and in their
comrades,[3]
we recog-
nize in them the closest affinity of ideas with our own… It is known that the incar-
nations of this spirit are only of Aryan-Germanic (Galilei?)
blood…”[4]
Well, yes,
it does usually start in the head!— And thus I wish you good relaxation for the rest
of the vacation.
With best regards,
Peter Pringsheim.