Science Fair Project Encyclopedia
A comb is a device made of solid material, generally flat, always toothed, used for staightening and cleaning hair or other fibers.
Combs are among the older tools known to mankind, having been found in very refined forms already in settlements dating back to 5000 years ago in Persia - possibly at the height of the first major Indo-European migrations.
It can be argued that combs do not have only value as cosmetic implements. Combs may have given users an evolutionary advantage by helping in the endless fight against parasites. In fact, Indo-European or otherwise, there are no known traditional civilizations that ignore the use of combs, even those whose members have hair that is quite hard to comb.
The term is applied in English also to
- the fleshy crest atop the head of many species of birds (hens et al.)
- the ridge or reinforcement in the same position on steel helmets
- a periodic, sharp spike or dip pattern in a signal
- the thick, semi-flexible water-filtering structures used in filter-feeding by baleen whales, which are if anything closer to what one would call "brushes".
Alternative uses of combs include:
- Keeping long hair in place.
- Decorating the hair.
- Keeping a kippa in place.
- Separating cotton fibers from seeds and other debris. The cottin gin, a mechanized version of the comb, is one of the machines that ushered the Industrial revolution.
- Making music, by dramatically increasing the high-frequency harmonic content of the hum produced by the human voice box, and modulating the resulting spread sound spectrum by changing the resonanting frequency of the oral cavity. This is accomplished by stringing a plant's leaf or a piece of paper in one side of the comb and humming with cropped lips on the opposite side. This was the inspiration for the kazoo.
- Annoying people by making monotonous noises plinging repetitively at comb teeth of identical length and harmonic qualities. Boring as this may seem, it was the inspiration for a kind of comb with teeth of varying length, which eventually evolved in the carrillon, or music box.
Combs are also a favorite spot for police investigators to collect hair and dandruff samples that can be used in ascertaining dead or living people's identities, as well as their state of health, toxicological profiles, and so forth.
Sharing combs is a common source of parasitic infections, as one user can leave a comb with plenty of eggs or even live parasites, facilitating the transmission of lice, fleas, crabs, mites, fungi, and other undesirables. While these parasitic infestations are usually only mildly uncomfortable, they can also act as a conduit for more serious illnesses, such as the Black Plague, that killed one third of all Europeans in the 14th century.
There are no known strictly religious meanings for the use of combs, although these tools are mentioned in various religious scriptures.
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