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Needle etching
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Needle etching was once of the earliest mechanized glass etching processes. The "Geometric Etching Machine" was invented by John Northwood in the early 1860s, and it or variations of it were used well into the 20th C. (Hadjamach, 1991; shows a photo of it pg. 183).
The machine used complicated gearing to move a needle or set of needles over glass that had been covered in resist (such as beeswax) that protected it from the effects of acid. The object was then dipped in acid, which etched the pattern that had been created by the needles.
The motion of the needles followed a template, and the pattern is repeated again and again, with the needles never leaving the glass. There are no "loose ends" in needle etchings. The lines are also of uniform width throughout the object.
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