dielectric constant apparatus
Date: 1890-1915
Inventory Number: 3952c
Classification: Electrical Apparatus
Dimensions:3 × 18.5 × 2.8 cm (1 3/16 × 7 5/16 × 1 1/8 in.)
DescriptionTwo glass rods with brass mounts, most likely binding posts, at the top (a and b); two tarnished brass tubes with dials at one end and a thin length of rod extending from the other end (c and d).
Bottom mounts of glass tubes are cylinders on flat bases with holes on either side of the base. Top mounts are cylinders with three holes penetrating the diameter. Each hole has a corresponding screw with a circular ridged head. That for the bottom is on one side, that for the middle is on another, and that for the top was on top of the cylinder.
Brass tubes have cylinders, possibly of ebonite, at the top and dial pointers in the shape of Ls. Jutting out of the tubes perpendicularly are smaller tubes with holes through their diameters. Lengthwise along the bottom part of each tube are four slits distributed evenly around the circumference. The tubes culminate in larger metal cylinders, with ridged rings around their midpoints. Thin blue rods with circular caps are inserted into the tubes at the lower end.
Originally kept in decayed brown cardboard box, now discarded save for the box top with inscriptions.