C A L E N D A R 1 9 2 1 4 3 1
Feb 3 ALS from Johannes Classen. He found that when looking
for Ampère’s molecular currents in glass-hard steel, the
results are influenced by the sharpness of the hysteresis
curve. By keeping the coil fixed, its rotation becomes infi-
nitely small, and the impulse from the elementary magnets
to the iron core of the coil must be transmitted by a resis-
tance in the iron to the gyroscopic motion of the elementary
magnets, i.e., the resistance to reversal of magnetization
(hysteresis) is the cause of the transmission of this impulse.
TLS from Edouard Guillaume. He endeavors, yet again, to
convince AE of his system of space coordinates and of Wil-
ligens’s time coordinates. [11 554].
Participates in the general meeting of BNV in which it is
decided that AE, Harry Kessler, and Otto Lehmann-
Russbüldt should go to Amsterdam to convey a message of
the BNV to the International Federation of Trade Unions.
BNV Report 1921.
Feb 4 Attends the ballet “Josephslegende” by Richard Strauss
together with Harry Kessler, coauthor of the scenario with
Hugo von Hofmannstahl. Kessler 1961, pp. 240–241.
ALS from A. Frey Samsioe. Asks whether, when we ascer-
tain a rotation of the Earth by means of Foucault’s pendu-
lum, the rotation is a motion with respect to the Sun, the
stars, or to something else. [25 246].
Feb 5 TLS from K[arl] Hönn. Solicits article for the Easter issue
of the monthly Schweizerland. Offers a maximum honorar-
ium of 200 francs per printed sheet. [43 929].
ALS from Maurice Solovine to IE. Apparently his letter to
AE with an affirmative answer has been lost. He had already
acquired a copy of Einstein 1920j and has completed its
translation into French. Asks for arrangement with Springer,
and for further manuscripts. [21 129].
Feb 6 TLS from Robert Schorr. Solicits opinion on Johannes Clas-
sen as candidate for the chair of theoretical physics at the
University of Hamburg. [8 403].
Feb 7 In the 1921 state budget, 200,000 M are allocated for the
tower spectrograph and an additional 18,000 M for its main-
tenance. Kirsten and Treder 1979b, No. 366.