Science Art: With this electrolytic cell as little as a milligram of various heavy metals may be precisely determined, 1922

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Early electronics: a cell for isolating minute quantities of heavy metals, apparently by zapping a drop of a solution under a powerful microscope and seeing what’s left behind. (Though this looks more like a mechanism for getting droplets of heavy metals to rise into a pipette by heating and cooling the water underneath and getting the warmed solution to touch a copper wire inside the glass capillary – the slender tube coming off at an angle. Just a guess.)

Taken from The Bell System Technical Journal (1922), via Internet Archive Book Images, via
archive.org, via Wikimedia Commons.