Different fibers require different kinds of drop spindles for turning it into thread by hand. The short fibers of cotton (about an inch long) require a small, fast spindle. Wool requires a heavier spindle with a pretty large whorl (the circular disk) that provides enough momentum to compress the springy fibers. The long fibers of flax allow it to be spun on long spindles with whorls of relatively short diameter.

These flax spindles are probably from the late 19th century and come from Bulgaria. Their stone whorls provide rotational momentum and stabilize the axis of the spindle. Loose spindle whorls are frequent archeological finds around the world, as they tend to be made of durable materials such as stone or fired clay (unlike spindles, often made of wood). The lead whorl in this vitrine was found in England outside of Essex, where such medieval whorls are commonly found.

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