Thanks to an off-the-wall request by patron Sarah Clarke, Edinburgh's Filmhouse is offering several opportunities for jazz fans to bone up on a subject that has received a great deal less coverage than it deserves: women in jazz. The lives of the leading female jazz singers are well-documented, but their instrumental sisters have, generally speaking, been consigned to obscurity. Filmmaker Greta Schiller set out to right that wrong with her 30-minute 1986 documentary International Sweethearts Rhythm - the first of a double bill of her films.

The International Sweethearts of Rhythm was a non-white, all-female swing band which toured the States and Europe with much success during the war years.

Led by glamorous singer Anna Mae Winburn, it was more than a novelty band and boasted some superb musicians, among them tenor saxophonist Vi Burnside, who is described by the Guinness Who's Who of Jazz as ''a major jazz talent'' who ''would have been ranked among the finest of the day'' had she been male; Pauline Braddy, a drummer admired by the better-remembered Big Sid Catlett and Jo Jones, and red-hot trumpeter Ernestine ''Tiny'' Davis. Davis, who was nicknamed ''the female Louis Armstrong'', is profiled along with her lover of 42 years, fellow musician Ruby Lucas in the second Schiller film in the double bill, Tiny and Ruby: Hell-Divin' Women (1988).

The feisty wee trumpeter recalls how she was headhunted by Count Basie's Band, one of the leading big bands of the day, but refused to quit the Sweethearts.

Formed in 1939, The International Sweethearts of Rhythm evolved from a swing band of pupils at a school for the poor and orphaned in Piney Woods, Mississippi. The 18 women members described themselves as ''international'' because they came, as their names suggest, from a broad spectrum of ethnic origins. There were a few white musicians in the band, but because of the strict segregation laws, they often had to pass as black. While they were not as popular as Ina Rae Hutton's all-female band, the Sweethearts were, according to the Guinness Who's Who of Jazz, not only ''more accomplished musicians'', but also ''one of the best big bands of the swing era''. The pinnacle of their success was a tour of American bases in Europe towards the end of the Second World War when they also played the Olympia Theatre in Paris and broadcast on the Armed Forces Radio Service. The band broke up in 1949, and

Anna Mae Winburn formed a new group which lasted into the mid-1950s.

Schiller's documentary came about as part of a movement to write women back into jazz history. The film tracks down and interviews various surviving Sweethearts and chronicles their brief but impressive reign as the top girl band of the day, with archive footage of them in action. For genuine, old spice girls, look no further.

n International Sweethearts of Rhythm and Tiny and Ruby: Hell-Divin' Women are showing at the Filmhouse at 3pm today and at 6pm, 7.30pm, and 9pm tomorrow.