Photo by David Friend Productions, San Diego, California
SINGLE BARREL VACUUM PUMP & BELL JAR by ALOIS KREIDL
10-005. Czechoslovakian, early 1st quarter 20th century, with a brass trade label on the base for "ALOIS KREIDL, PRAGUE." Heavy maple veniered base, 18 3/4" x 12" x 2 3/8", with a single 7 5/8" tall x 2 3/4" diameter glass vacuum cylinder mounted vertically in a lacquered brass framework on one end of the lacquered brass base, with brass gear racks and a brass crank handle, 15" tall overall. The vacuum cylinder is connected to the 8 3/4" diameter glass covered brass bell jar plate on the other end of the base, with an 12" tall vacuum mercury manometer assembly mounted in the center of the base. Also included is a period 10 1/4" tall heavy glass bell jar, with an electric bell mounted inside that is connected to terminals through a rubber stopper in the top (used for a demonstration that sound does not propagate in a vacuum). This attractive single barrel vacuum pump is in very good overall condition.
