Butter churns come in different shapes and sizes. This one is a glass jar, about 19cm high, with a red metal lid. A cog mechanism, with a handle that turns wooden paddles inside the jar, is mounted on the lid. This mechanism was in use by the end of the 19th century and was still being used in the1950s, with variations on the paddles and design.

This jar does not fit the lid perfectly and it is possible that the lid was made to fit an standard fruit jar. The original jar may have been broken, as many of this type of churn came with their own jars. The mechanism on top of the jar is made in cast iron - parts of this one have been broken off. Opposite the handle is a grip to hold the jar steady, and above the larger cog is a bar to protect the mechanism.

Cream is made by leaving milk to stand overnight to let the cream rise to the surface. Cream (and milk) sours if left long enough, especially in the summer. Sour cream added to fresh cream results in all the cream souring. If the cream is sour enough it does not take long to make butter. Butter can be made simply by pouring soured cream into a container and shaking it. However, churning (turning the cream over and over by some mechanism) is the most efficient way. When globules of butter appear the excess liquid is poured off, and what is left is butter. This is then formed into blocks or rolls with butter pats.