Chalk line made by the Seymour Products Company of Seymour,Connecticut. The company may date back to 1878 when, as the Seymour Manufacturing Company, it made brass, copper wire for telephones and telegraphs, and German silver for table silverware. The company is best remembered for its production of 30-round magazines for Thompson submachine guns during World War II: over the course of the war it produced 12,375,608 of them, more than any other single manufacturer. After the war, they seem to have mostly made chalk lines. Quite a comedown.