Traditionally the fine mesh required for photo engraving was produced mechanically but Clapham perfected a photo-reduction and electrolytic method to produce membrane-like metal plates with thousands of invisibly small holes.
12.
One of Kemtron's product lines, photo engraved car kits, particularly the flats, often used zinc ( or a very high zinc content brass ) sheet, as opposed to brass.
13.
The company was in the business of photo engraving " in line or half tone or zinc or copper . " They produced " every kind of a plate used on a letter press . " The firm had recently opened a new foundry and A . W . Hall was manager.
