antique electrical test meter wood case hinged box

Description

antique electrical test meter wood case hinged box.
wonderful electrical instrument in latching, mahogany case with original finish and nickel-plated appointments.
test probe with storage clip can be inserted in 3 sockets marked "black red blue"
two long dial scales run the length of the box, each contains a thin bare wire stretched across its length.
one of these two wires (the one on the front scale) is disconnected/broken at left end.
center bar contains a telegraph key type momentary contact at the left, and a round bubble lens in the center with dial scale marked
+ and -.
to the right on the center bar are 3 sockets for the probe marked "black red blue".
at the far right edge of the box are 3 screw terminals for the probe and two bare wires mentioned above.
a nameplate on the inside of the lid appears to have been removed in order to apply a service sticker marked
"5-51 serviced by christie laboratories cleveland, ohio", and the plate was never put back in place.
the box has a locking catch; but there is no key.
4 padded feet on bottom and 4 on right end of box; though two of the feet on the right end have worn/broken off.
appx. 9 1/2 " x 5" x 5".
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