Brownies in Faerie Lore

Brownies are a kind of faerie.  They're in the category of Hob, a "house spirit" in the U.K. (Possible connection with Hobbits?)
A Hob may be a word that evolved from the English given name of Robin, related to Robin Goodfellow, another name for a Brownie in southern England. 
Hobs appear to be related to the Swedish Tomte or Tomtars, with a history similar to Ireland's Tuatha De Danann.  In both cases, these faeries retired to the "hollow hills" or Brughs: Hollow faerie mounds in which several families live (or lived).
A Hobgoblin is a cousin of the Brownie, and -- perhaps because he's more of a practical joker -- the Hobgoblin is sometimes considered a poltergeist rather than a faerie. 
Dobby in the Harry Potter stories seemed to be related to hobgoblins; a Dobie is another term for a brownie, in some areas, or it can mean a ghostly entity in other areas.
Brownies are usually:

Solitary faeries, seen alone or in very small groups.
Male (but some are married, and that's usually the only time a female Brownie is seen).
2 1/2 to 3 feet tall, but some are described as being six or seven inches tall.
Naked and very hairy, or dressed in brown clothing, with shaggy brown hair.
Associated with a pond, pool or stream. (Brownies may have webbed fingers, making swimming easier.

Brownies may become attached to a family or one member of the family.  Brownies usually prefer rural homes and farms, where they may work at night, farming or cleaning.
Brownies are most prevalent in northern England and in Scotland.
Favorite Brownie foods include a bowl of cream or rich, whole milk; cakes with honey; and corn muffins, possibly served with honey.
However, you must be very clear when you set out the treats for the Brownie:  This is not a payment for his (or her) work.  In most cases, if you try to pay a Brownie, he'll leave.  He doesn't work for payment.
In contrast, areas such as Lincolnshire have Brownies that like to be paid, and specifically with clothing.  On New Year's Eve, Brownies in Lincolnshire have each been paid with a traditional white linen smock.
Other Brownies will leave if you try to give them any kind of clothing.  This raises the question: Do they resent the payment, or does the gift of clothing set them free, as with Harry Potter's Dobby?
Similar names and words
"Brownie" may be spelled Browney, Brouny, or Browny.  However, the Brownie should not be confused with the Cornish Browney, a spirit or faerie that protects (or perhaps is) the bees.
Brownies may be related to the Brown Man of the Muirs, a spirit or faerie that protects and guards the wild beasts along Scotland's Border Country.
Brownies and devils
In his book, Daemonologie, King James I said that brownies are devils, but they do no harm.
Devil's Bridges
Devil's Bridges are a category of bridge from Medieval (not Roman) times.  They exist in England and in Europe. 
The name may come from one of three sources:
1. The bridge was built by the Devil.
2. The bridge was built with the Devil's help.
3. The bridge proves the might of the bridge builders, and makes less of the Devil.
This kind of folklore relates to fairy (faerie) tales.  In the typical story, the bridge builder makes a deal with the Devil:  If the Devil will build the bridge himself, in one night, the Devil can then take the soul of the first person to cross the bridge.
After the bridge is built, the Devil tricks the bridge builder into crossing the bridge, so the bridge builder loses his own soul as payment.
This relates to stories such as Rumplestiltskin, in which flax is spun into gold overnight, and the young woman must guess the name of Rumplestiltskin, or later give up her first child to the dwarf or goblin. (Of course, she outwits Rumplestiltskin and declares his name, so she forfeits nothing.)
One bridge called "the Devil's Bridge" is in Carnforth, in Lancashire, England.
For more information about faeries, visit Faerie Magick (dot com).
Music: Moods of Man, written and orchestrated by James Underberg.