Chemical etching (also called photochemical etching, photo etching, or chemical milling) is a precision manufacturing method ...

IIIF provides researchers rich metadata and media viewing options for comparison of works across cultural heritage collections. Visit the IIIF page to learn more. Platemark: 15 × 22.5 cm (5 7/8 × 8 ...

If you were building a recreation of the James Watt micrometer, where would you start? If you’re [rasp], the answer would be: “Spend a year trying to find the best way to make etched brass discs.” ...