This is a view of a typical naval lanyard. Lanyards were issued to all crewmen along with a single-bladed navy pocketknife, which was generally attached to the end of the lanyard. The other end of the lanyard went around the sailor's next, and could be drawn tight by pulling a "turk's head" knot as tight to the neck as was comforatble. By attaching the knife to the lanyard, the chance of dropping the knife overboard or losing it in some other manner was greatly reduced.
One of the few navymen who did not attach a knife to their lanyard was the boatswain or "bo'sun" who would attach his "pipe" to it. The pipe was a high-pitched whistle-like instrument which was used to issue certain orders.
The lanyard was approximately one yard in length (doubled, and therefore
was made from about two yards of material) and made of a white cloth tape.