▁Ar ound ▁this ▁time , ▁compos ers ▁of ▁classical ▁music ▁developed ▁a ▁strong ▁interest ▁in ▁collect ing ▁traditional ▁songs , ▁and ▁a ▁number ▁of ▁out standing ▁compos ers ▁carried ▁out ▁their ▁own ▁field ▁work ▁on ▁traditional ▁music . ▁These ▁included ▁Per cy ▁Gra inger ▁and ▁Ralph ▁V aug han ▁Williams ▁in ▁England ▁and ▁Bé la ▁Bart ók ▁in ▁Hung ary . ▁These ▁compos ers , ▁like ▁many ▁of ▁their ▁prede cess ors , ▁both ▁made ▁arrang ements ▁of ▁folk ▁songs ▁and ▁incorpor ated ▁traditional ▁material ▁into ▁original ▁classical ▁compos itions . ▁The ▁Lat v iju ▁d ain as ▁are ▁extens ively ▁used ▁in ▁the ▁classical ▁ch oral ▁works ▁of ▁Andre js ▁Jur ā ns , ▁J ā nis ▁C im ze , ▁and ▁Em ilis ▁Mel ng ail is . ▁ ▁North ▁America ▁▁ ▁The ▁advent ▁of ▁audio ▁recording ▁technology ▁provided ▁folk lor ists ▁with ▁a ▁revolution ary ▁tool ▁to ▁preserve ▁van ishing ▁musical ▁forms . ▁The ▁earliest ▁American ▁folk ▁music ▁sch ol ars ▁were ▁with ▁the ▁American ▁Fol kl ore ▁Society ▁( AF S ), ▁which ▁emer ged ▁in ▁the ▁late ▁ 1 8 0 0 s . ▁Their ▁studies ▁expanded ▁to ▁include ▁Native ▁American ▁music , ▁but ▁still ▁treated ▁folk ▁music ▁as ▁a ▁historical ▁item ▁preserved ▁in ▁isolated ▁soci eties ▁as ▁well . ▁In ▁North ▁America , ▁during ▁the ▁ 1 9 3 0 s ▁and ▁ 1 9 4 0 s , ▁the ▁Library ▁of ▁Congress ▁worked ▁through ▁the ▁offices ▁of ▁traditional ▁music ▁collect ors ▁Robert ▁W ins low ▁Gordon