Here is another interesting accidental find, this time from papers at the Library of Congress.
In 1917, Professor S.C. Kiang, an academic at the University of California in Berkeley, traveled to China to procure for the Library of Congress valuable Chinese manuscripts relating to geography, and on his return, reported on his doings in China to Herbert Putnam, the Librarian of Congress. At the bottom of the eighth page of the report, which I recently found in the Library of Congress’ own internal records, Professor Kiang displayed a Chinese seal design stamped in ink, which, he said, “comprises the title of the Library of Congress.” A well-known Chinese engraver who had made seals for several Chinese presidents, had also made this seal for Kiang as a gift, using characters of the “ancient bell style.”
Such seal stamps have been commonly used in China and Taiwan for centuries to sign documents, artwork and other papers. Stamp engravers typically make such seals from stone, but they can also use plastic, ivory or metal. The ink used is a red paste.
You can read more about the art and usage of Chinese seals here: