touch-needle

English

Noun

touch-needle (plural touch-needles)

1. A small bar of gold and silver, either pure, or alloyed in some known proportion with copper, for testing the purity of gold or silver articles by comparison of the streaks made by the article and the bar on a touchstone.

Part or all of this entry has been imported from the 1913 edition of Webster’s Dictionary, which is now free of copyright and hence in the public domain. The imported definitions may be significantly out of date, and any more recent senses may be completely missing.
(See the entry for “touch-needle”, in Webster’s Revised Unabridged Dictionary, Springfield, Mass.: G. & C. Merriam, 1913, →OCLC.)