JF Ptak Science Books 
In the “Spirit of Discovery” section of the British weekly magazine The Mirrour of Literature, Amusement, and Instruction for 22 October 1836 is a short notice on the “physiognotype”, “a machine for taking casts, lately invented by a gentleman in Paris” [The patent application for this device seems to be the work of Richard Rettford, UK patent # 6732, 1834.] We’re accustomed to these devices now as they’ve been for sale in toy shops for decades—but in 1836 it was a real breakthrough for making instantaneous three-dimensional models of small things. In 1836 there really wasn’t any simple way of producing a direct, proportional model like this in 3-D except for encasing it in plaster and then casting from that mold. Two-dimensional modeling was easier, and there were numerous devices constructed for this purpose as people pursued the still-hot rage of physiognomic forecasting, with simpler means (like shadow portraits) being hundreds of years earlier. (Photography remember is still three years away from being announced and another few years from being sort of accessible to middle-class folks.)
This device was simple and cool, and it worked. It was basically a board with a mesh of tiny holes drilled into it through which were placed knitting needles (it looks as though it was 12” around or so and four inches deep), bound in wood, with the enclosure encased by a bladder of warm water (“to ensure that the needles moved with the greatest facility”)—this last bit was really a good idea. You were left with a “brush of needles”, very densely packed, and very easily disturbed. The author writes that the process took about two seconds, didn’t hurt at all, and caused “a sensation that cannot well be described”. (Though he did state that if the instrument wasn’t warmed by the water the process would’ve felt like putting your face in the snow…does that mean it felt like putting your face in warm snow?)
I’ve tried, briefly, to see where this invention went, but it seems not to have advanced far beyond the reach of quack medical practioners and magicians. It seems as though something like this could’ve been useful in the machine shop for modeling (replacement) parts without having to take the machine itself apart to do it. I guess that it could’ve been used by haberdashers, cobblers, and all sorts of other craftspeople and small manufacturers, but it seems as though it actually wasn’t. It looks like a dandy piece of thinking, to me.
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