Remember that rainy evening, I threw you out
With nothin' but a fine tooth comb?
– Hughie Cannon¹, 'Won't You Come Home, Bill Bailey?', 1902

We sing the praises of the humble comb: an indispensable implement of personal grooming for all but the bald and beardless. You may have one in your pocket or bag. Otherwise, your hair would become hopelessly tangled. Depending on the style of your hair, you may have one of a variety of combs, from the all-purpose comb for hair that grows down to the pick comb for hair that grows up and out – or the small one for grooming the beard or moustache. Chances are, that all-purpose head comb has two sets of teeth. You may also own what is called a 'fine-toothed comb.' Those fine teeth have a serious purpose beyond grooming: they trap head lice and their nits.

History

India-rubber combs, now so extensively used, are manufactured by pressing the caoutchouc in moulds to the required form, and afterwards vulcanizing it, or combining it with sulphur, by which means it attains great hardness.
– The Bel Air, Maryland Aegis & Intelligencer, 19 May, 1865, p1

Combs are among the artefacts found by archaeologists, going back at least 5,000 years to ancient Egypt. They are also found in digs in Persia and South America. These combs are usually made of wood, bone, or ivory, and are often of the fine-toothed variety. A lot of times, archaeologists find very old remains of nits and lice stuck between the teeth. Finding ancient dead insects is one of the many little perks of being an archaeologist. They show us that humans have had the sense to comb their hair for a really long time – and lice were a bother to our ancestors as well as the local school board.

Combs made of wood, bone, and ivory are decorative. They're also relatively expensive, being labour-intensive to make. They have another drawback: when you drop them, they can break. The inventive 19th Century set out to solve the problem of combs that break. Scientific minds everywhere focused on the goal of the unbreakable comb.

The Goodyear brothers solved the problem in 1839 with vulcanised rubber. Vulcanising rubber meant heating it with sulphur. The result was an unbreakable comb – or at least, one that didn't break or lose teeth when you dropped it. By the middle of the 1850s, rubber combs were affordable and popular tools for grooming and chasing nits. Their company even made the kind of decorative combs that stayed in women's hair.

In 1863, John Wesley Hyatt of Starkey, New York, was experimenting with nitrocellulose when he came up with what he called celluloid – at about the same time Englishman Daniel Spill came up with pretty much the same thing, only called Xylonite. The ensuing patent dispute was settled by the court saying both inventors had essentially improved on something called Parkesine, so the real inventor was Englishman Alexander Parkes, who had done his inventing in 1862. The court decided they should all just carry on making whatever it was they were making. Combs made of celluloid became popular, although some were also manufactured of xylonite and ivoride. Hyatt received his celluloid comb patent in 1878.

After the Second World War, plastics took over the industry. Combs made of polypropylene truly were unbreakable, and manufacturers complained that they had to wait for customers to lose them rather than break them. Teenagers continue to try to break them on Youtube and Instagram, possibly because they like a challenge, and barbers and hairdressers continue to do artistic things with them.