Sarah Pitt advertises in the Virginia Gazette in October of 1768 that she offers for sale "a great assortment of threads".  Some of the threads likely available were what we like to call "Tailor's" threads.  The 18/3 "Tailor's" Thread - Heavy is a perfect size for cording of buttonholes, or any other area where a very stout thread is required.

• These small spools are perfect for individual projects with 12 meters/39 feet.
• 18/3 "Tailor's" Thread - Heavy is available in Natural only.