Humboldt State University
Robert A. Paselk Scientific Instrument Museum
Pantechnical Mfg. Co.
Humboldt S-T-C; c.1926
Used to measure vacuum/pressure in the range of 1-120 mm Hg. The instrument is operated by comparing the heights of the two mercury surfaces in the U-shaped tube. The mirrored scale may be adjusted to provide a direct readout from the scale, eliminating the need for arithmetic.
The instrument is constructed of black painted wood. The base has a quarter-round bead on the top edge and is 6 5/8 x 5 3/8 x 3/4". It sits on four small rubber feet. An upright, 12 7/8"t x 3 3/8"w, is attached with its front face centered on the base. A 13-0-13cm scale, etched into a mirror, is held with small brackets onto a wooden slide on the left side of the upright. An open ended manometer tube loops around the scale and then down to a stopcock which is in turn connected to a "T" running along the bottom of the upright. The manometer tuber is held in place with six small trefoil pattern-end, nickel plated brass straps attached with miniature screws. A nickel plated brass manufacturer's tag with raised polished letters against a black background is pinned in the center front of the base. The legend is as follows: TRADE PANTEC MARK/ PANTECHNICAL MFG. CO. / BERKELEY -CALIFORNIA. There is an oval brass tag, stamped HUMBOLDT S-T-C / 2108, attached to the top of the wooden stand with two brass pins. The instrument is in fine condition noting that the mirror is in need of resilvering, the wood shows through the paint on some edges and there is a break, repaired with rubber tubing in the manometer tube between the stopcock and the "T".
The catalog description is for a similar instrument sold by the Braun Corporation in 1934.