Oakum is a preparation of tar

Tar

Tar is modified pitch produced primarily from the wood and roots of pine by destructive distillation under pyrolysis. Production and trade in tar was a major contributor in the economies of Northern Europe and Colonial America. Its main use was in preserving wooden vessels against rot. The largest...

red fiber used in shipbuilding, for caulking

Caulking

Caulking is one of several different processes to seal joints or seams in various structures and certain types of piping. The oldest form of caulking is used to make the seams in wooden boats or ships watertight, by driving fibrous materials into the wedge-shaped seams between planks...

 or packing the joints of timbers in wooden vessels and the deck planking of iron and steel ships, as well as cast iron plumbing applications. Oakum was at one time recycled from old tarry ropes and cordage, which were painstakingly unraveled and taken apart into fiber; this task of picking and preparation was a common penal occupation in prisons and workhouse

Workhouse

In England and Wales a workhouse, colloquially known as a spike, was a place where those unable to support themselves were offered accommodation and employment...

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In modern times, the fibrous material used in oakum is derived from virgin hemp

Hemp

Hemp is mostly used as a name for low tetrahydrocannabinol strains of the plant Cannabis sativa, of fiber and/or oilseed varieties. In modern times, hemp has been used for industrial purposes including paper, textiles, biodegradable plastics, construction, health food and fuel with modest...

 or jute

Jute

Jute is a long, soft, shiny vegetable fibre that can be spun into coarse, strong threads. It is produced from plants in the genus Corchorus, which has been classified in the family Tiliaceae, or more recently in Malvaceae....

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