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Galvanometer Ayrton Shunt
Universal Ayrton Leeds & Northrup shunt for any galvanometer. . Decreases galvanometer sensitivity by shunting a selected fraction of the input current to bypass the galvanometer. Shunt resistance affects galvanometer damping.
Date Unknown.
Model No. 2116, Serial No. 275073
Induction Coil
Induction coil probably manufactured or at least marketed by Cental Scientific Company. The coil matches the image of another coil with a Central Scientific nameplate. The nameplate is missing from our coil, but the mounting spots are visible. Nameplates containing Central Scientific Company were probably manufactured between 1900 and 1909 with those containing the trademark CENCO manufactured after 1909.
Cenco Density Ball and Box
Density Ball floats in tap water, sinks in water at 85 F or higher. Label on box contains CENCO trademark indicating ball was purchased after 1909; otherwise, date is unknown.
Signal Corps Test Unit I-176
Signal Corp Test Unit I-176, serial no. 0238, containing a Triplet Elec. Inst. Co. multimeter. The Physics Department probably obtained this unit from army surplus in the decades following World War II.
L. Bradley Circular Resistance Box
Circular resistance box manufactured by L. Bradley & Co. in Chicago. Patent date is Jan. 7, 1873. Construction of box consistent with 1870s technology. Box was probably used in trouble shooting telegraph or possibly telephone lines. We have no further information about the box.
