Model 71 Measuring Device

Completed September 1998

The instruction card attached to this instrument says it best:

"The Model 71 is a portable standard for calibrating once-living and non-living organic substances. It accepts a wide range of inputs and may be used with a minimum of surveillance... Only a small quantity [of the organism] is needed; a small portion may be removed with little harm to the subject."

While the Model 71 performs its intended functions with hopeful grace, it leaks out hints of its cultural inheritances and intents (intentional and otherwise). Some things are reasonably visible, but others might remain obscure to those outside the priesthood; this instrument of deduction is tightly focused and utterly unaware of its own context, unsure of its own authority, unable to relax and just get the job done.

A sample is prepared, according to excruciating instructions on a card in the front cover, and placed into the complicated and delicate probe mounted in a little door in the front of the machine. The operator carefully adjusts a calibration control as instructed, and the machine is set to run; the Model 71 then performs a number of calculations based upon actual electrical measurement of the sample.

(If none of this manual preparation is actually done and the machine is left idle, it will occasionally find things to do of it's own accord.)

Physically, the Model 71 is constructed of excruciatingly correct and luscious materials and components; veneered cabinetry, deep-etched copper plate, bakelite knobs; delicate glass, rubber, and nickel-plate probe assembly, and ancient and beautiful electro - mechanical graphical displays (for presenting the symbolic results of the calculations) and an optical "single plane" display for operational status.

The cabinet once housed a Beckman portable laboratory pH meter; the sample-measuring probe assembly mounted inside the chamber on the front of the unit are original, though modified to use nontoxic solutions. Test vials and a bottle of reagent needed for testing (including a recipe for the preparation thereof) are contained in a pouch within the removable cover. The front panel is quarter-inch-thick copper plate, deep-etched and corroded, hand-machined to accommodate the display units and controls. All other hardware is brass and new-old-stock phenolic.

Mixed media (wood, brass, electronic components), 10.5"h x 11.25"w x 8"d, approx. 15 lb.





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