Run through the mangle

I wish these calculations had been performed by steam.
— Charles Babbage

I'm back to my ongoing theme of gears and machinery. And I'm also back to my ongoing theme of refraction spectra. Appropriately enough, I spent most of today being processed through bureaucratic machinery (grind grind crank crank arrgh), but ended up with a more-or-less positive result. Sometimes I feel that my imagery is altogether too simple and obvious.

Calculation by Steam



Frame-Robert formula. Nine layers, two of them masked.