The American academic Francis J Child devoted much of the latter part of his life to collecting and studying traditional ballads. His first publication on the subject was English and Scottish Ballads, 8 vols published in 1857-8. This was revised and augmented in a collection of 305 British ballads, published in 5 volumes in 1882-1898 as The English and Scottish Popular Ballads, often known as the 'Child Ballads'. When I first set up this database, the books were long out of print, but they were republished in 2003 by Dover Press. In addition, copies of the 19th-century edition are now available on the Internet Archive: vols I, II, III, IV, V. Copies of the original 1857 vols are also available on Google Books: I, II, III, IV, V, VI, VII, VIII. See Wikipedia entries on Child and the ballads.
This database, based on files provided by Cathy Lynn Preston of the University of Colorado, provides the text of those ballads for browsing and searching; it does not provide Child's scholarly commentary. Enter your query, then click on a title to view the text of the ballad concerned.