If you've ever passed a town hall or a student union on a Saturday night and heard the sounds of fiddles, banjos, and a voice calling ''hands four from the top,'' you've probably stumbled upon the latest fad - country dancing.
From Murphreesboro, Tenn. to Mendocino, Calif., this revival of a 300 -year-old social activity is quietly sweeping the country.
Since 1970, says Jim Morrison, a country dance historian and caller, branches of the Country Dance and Song Society of America have doubled, and hundreds of other dance groups have sprung up, most of them in the last six years.
In southern Vermont it is possible to dance six consecutive nights from town to town.
One caller reports that attendance at a Baltimore dance has grown 30 percent in one year.
What is this new fad? Country dancing is not easy to define. For one thing, ''country'' doesn't mean rustic. It is taken from the French ''contre,'' meaning against, and refers to a type of line dance, called contras.
Every 60 miles it's something different. Ask someone at the Community Center in Mountain Grove, Va., what he thinks country dancing is and he probably tell you, ''Big Circles,'' while in Brattleboro, Vt., the answer may be ''contras.''
Scottish, Irish, Western squares, and swing dancing are also part of the country dancing family. Square dancing, also known as club squares, is a derivative of traditional Western squares, and is a separate group.
Today's country dances are the offspring of the cotillions, minuets, and long-ways dances that enjoyed widespread popularity among peasants and royalty alike in Europe. The first American settlers packed these dances along with their china and plows, and the dances formed the backbone of American social life for 200 years. The high point of their week was the regular Saturday night dance.
Preserved in some rural areas, country dancing died out in cities and towns in the early 1900s when couple dances such as the fox trot, the mazurka, and the two-step became the rage.
After a long hibernation, it was revived in New Hampshire when some college students stumbled upon a traditional contra dance, and within two years it became popular among New England young people.
During the 1970s, country dancing spread across the United States, aided by traveling callers, summer dance camps, and dance festivals.
Another popular form, English country dances, was reviving at the same time the American ones were dying out. Dancing had long been extinct in the cities when an English antiquarian, Cecil Sharp, discovered some of the old dances in the outlying regions and revived them through workshops.
A young English bystander at one of the workshops, May Gadd, decided on the spot to make country dancing her life's work. She came to the United States to join the dance groups here and later helped form the Country Dance and Song Society of America to preserve English and American dancing. In 1937, she helped start Pinewoods dance camp, the oldest folk dance camp in America.
Why did an activity that had lain dormant (except in rural areas) for half a century suddenly regain popularity?
One explanation is Americans' newfound appreciation of their heritage, as reflected in the surge of interest in quilts and wood stoves. But dancers also like country dancing because it's a pleasant way to spend Saturday night. The dances are designed as mixers, and women and men alike are encouraged to choose new partners frequently. More advanced dancers take special care with beginners, and few people sit out unless they choose to.
Country dancing appeals to a variety of people, from ''apple-pickers to computer operators,'' says Todd Whittemore, a Boston caller. Callers (those who lead the dances) range from a federal circuit judge who organizes the dance in Louisa, Va., to a carpenter in San Francisco.
Jim Morrison was hired to call a dance for a law firm's annual outing because , as the outing's organizer confided, ''it's the only activity they'll all agree on.''
As it did in pioneer days, country dancing today provides the nucleus for other social activities. Pre-dance potluck suppers are becoming increasingly popular. Lifelong, coast-to-coast friendships have formed through dancing, and some have even resulted in marriages.
There is a strong feeling of support among dancers for encouraging the movement as a whole. A resident of Phoenix, Ariz., longed to continue dancing after returning home from a dance camp. After contacting the Country Dance and Song Society in New York for help in forming a local group, a prominent caller and a fiddler volunteered to fly from New York and hold workshops for her. Phoenix now has a thriving country dance community.
Ralph Page, a longtime New England caller, gives a good clue as to why country dancing is so popular today in ''The Country Dance Book'':
''Country dancing has been responsible for the friendship of town and country , young and old, beginner and veteran, 'high and low . . .' and all . . . may be in the same set together. It's a workable democracy, a rare find in these democratic days. And if you want to carry it further, you might even call it a pretty good design for living, too.'