THE OFFICIAL Washington record industry includes two august institutions, the Smithsonian Institution and the Library of Congress. The Smithsonian has gotten deserved attention for its two landmark historical sets on jazz and country music, but several years ago, the Library of Congress quietly issued its own landmark: 15 individual volumes under the general heading of "Folk Music in America."

The project, funded by the National Endowment for the Arts, was part of the Library's American Revolution Bicentennial and utilized commercial and private sources as well as the Archive of Folk Song's huge collection of recorded materials. Of all the bicentennial projects that flooded the country, it's hard to think of one more valuable, interesting, lasting or enlightening. It's an aural document that belongs, at the very least, in every library and school, though it also can provide hours of entertainment and education to individual listeners.

The thematically arranged selections span the history of recorded music (the earliest cut being a Yaqui Snake Dance recorded by a Harvard anthropologist in 1890). One hears songs in dozens of American dialects, as well as in French, Polish, Swedish, Spanish, Hebrew, Ukrainian, Russian and Italian.Throughout, one hears ordinary people making music that is immensely personal and important. It is music that transcends racial, regional and linguistic boundaries -- blacks constructing symbolic metaphors for the freedom struggle, immigrants loath to sever the values and ties with their Old Worlds, individuals moving out and up and, sometimes, back down, burdened by lovesickness, homesickness, poverty and prejudice.

What shines through is a rugged individuality, an inner strength expressed through music and lyrics. The material was recorded over the course of 85 years, in homes and fields, in prisons and churches, in dime-store studios and in those of labels like Columbia and RCA. Richard Spottswood's shaping provides a fascinating overview of "the backgrounds and interests, objects, activities and character" of America. To hear these albums is to catalogue our history and our concerns. And, like a camera, the tape machine makes history accurate, an increasingly important factor in understanding such disappearing traditions as ring-shouts and play-parties, border radio shows and other institutions that were once so familiar.

Many of the songs and themes are familiar. Folk music is after all a style of variations on the oral tradition, songs handed down from generation to generation, newly decorated and personalized along the line. It matters little whether it's blues or bluegrass, secular or sacred, Cajun, cowboy or Indian; the constants are humor gleaned from adversity, pathos and pain from the weight of history, pride in family and faith. One senses a country imploding with immigrants, celebrating renewal, bursting at the seams with new energies.

It's impossible to review such a massive anthology, so here's the merest hint of what's available on one volume, "Songs of Complaint & Protest (Vol. 7)": Mattie, Marthie and Minnie's old-time country singing on "You Can't Live With 'Em (And You Can't Live Without 'Em)"; calypsonian Wilmouth Houdini's admonitions, "Don't Do That To Me"; Chicago bluesman Bumble Bee Slim and Alabaman Jerry McCain and his Up-starts complaining about "Hard Rocks In My Bed" and "My Next Door Neighbor," respectively; Lester Flatt and Earl Scruggs' classic bluegrass tune, "Over the Hills to the Poor-house;" Ernest Stoneman and his Dixie Mountaineers prophesying the Depression with a 1928 ditty called "All I Got's Gone." Listening to these albums is like having a radio doubling as a time capsule; it leaves you wide-eared.

Each album contains 15 or 16 selections, with an instructive brochure that comes with transcriptions (and translations, where necessary), historical background and analysis and references to similar songs and guidance for further research. Within each album are folk forms that are accessible or obscure, idiosyncratic or obvious, propelled by familiar instruments or the dozens of ethnic and homemade variations that speak to America's cultural diversity.

The accents, rhythms and emotions evident in the folk tradition push through the limitations of recordings made in the '20s, '30s and '40s with less-than-exemplary equipment. There's really little difference between Luther Magby's 1927 recording of "Blessed are the Poor in Spirit" and Jimmy Murphy's 1951 "Electricity" and Leroy Selam's haunting, wordless Yakima Indian "Death Chant (Honor Song)" recorded in 1975. The feel, the heart of the matter has never changed and ultimately that's why folk music tells the best kind of history -- living history. Dick Spotswood and the Library of Congress deserve a tremendous thanks for reminding us of that with this seminal anthology.

Folk Music in America, 15 volumes, edited by Richard K. Spottswood

LBC1 -- "Religious Music: Congregational and Ceremonial"; LBC2 -- "Songs of Love, Courtship and Marriage"; LBC3 -- "Dance Music: Breakdowns & Waltzes"; LBC4 -- "Dance Music: Reels, Polkas & More"; LBC5 -- "Dance Music: Ragtime, Jazz & More"; LBC6 -- "Songs of Migration & Immigration"; LBC7 -- "Songs of Complaint & Protest"; LBC8 -- "Songs of Labor & Livelihood"; LBC9 -- "Songs of Death & Tragedy"; LBC10 -- "Songs of War & History"; LBC11 -- "Songs of Humor & Hilarity"; LBC12 -- "Songs of Local History & Events"; LBC13 -- "Songs of Childhood"; LBC14 -- "Solo & Display Music"; LBC15 -- "Religious Music: Solo & Performance." Available at the Library or by mail from The Library of Congress, Recording Laboratory, Washington, D.C. 20540. Individual volumes are $6.50 each; complete set is $85.00.