Reverend Francis A. Tondorf, S. J., and Rev. James B. Macelwane, S.J., examining a Cambridge-type vertical component Galitzen electromagnetic seismograph installed in 1923 at Georgetown University, Washington, D.C.. Wilip improved the Galitzen design in terms of temperature and pressure stability to make the Galitzen-Wilip. (J. B. Macelwane Archives, Saint Louis University)

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