Slow match or match cord is the very slow burning cord or twine fuse used by early gunpowder musketeers, artillerymen, and soldiers to ignite matchlock muskets, cannons, and petards. Slow matches were most suitable for use around black powder weapons because a slow match could be roughly handled without going out, and only presented a small glowing tip instead of a large flame that risked igniting nearby gunpowder.
The slow match attached to the lock of the matchlock gun was usually a length of hemp cord that had been chemically treated to make it burn slowly and consistently for an extended period of time. The rate of burning was approximately 1 ft (305mm) per hour. In practical use on a matchlock, both ends of the match cord were often ignited, as the flash of gun powder in the flash pan could often extinguish one end of the match cord, and the remaining end could then be used to re-ignite the firing end of the cord upon reloading the matchlock musket. To prevent dragging the match cord on the wet ground, a linstock was often carried and used, it being a forked wood support inserted into the ground and used for holding the end of the match cord farthest removed from the matchlock.
Many formulas for match cord exist, providing varying burn rates. The predominant chemical used was potassium nitrate, although sodium nitrate, and lead acetate also appear to have been used. Potassium nitrate, however, had an advantage over sodium nitrate, through being less likely to absorb atmospheric moisture.
Match cord was often used from the 15th Century until about 1630, when the flintlock started its rise to prominence. (The arrival of the snaplock after 1540 had only limited impact on match cord use, snaplocks generally being considered a peasant's weapon.) Match cord remained in use with limited numbers of match locks in Europe until approximately 1730, and in Japan until the early 1900's.
Modern-day slow match (used with replica matchlock firearms) is sometimes made of cotton cord, instead of hemp, due to legalities associated with growing hemp plants.
 See also
- Black match (quick match)
- Flash pan
- Fuse (explosives)
- Punk (fireworks)
- Touch hole