"The string quartet, for two violins...was one of the most widely-cultivated genres of chamber music during the Classical period, with...Haydn, Mozart and Beethoven all contributing substantially to the literature." The Rare Book, Manuscript, and Special Collections Library at Duke University Library has made available a lovely online collection of sheet music for the string quartet published between 1770 and 1840. Visitors interested in checking out the crisp PDFs of some very old works, should click on the link "Explore the Collection" on the left hand side of the homepage. The "Composer", "Title", "Publisher" and "Date" can each be viewed in ascending or descending order, and a thumbnail of the top page of the piece of music is also shown. The oldest published piece of music in the collection is from 1770 by Antonin Kammel.