Art museums often publish a journal, which includes papers primarily based on research about their specific collections. Since 2004, the Tate has been publishing its version online, as the Tate Papers. The tag-line on the Web site promises that the journal will "cover a wide range of subjects: artists, works of art and archives in Tate's collection, art theory, visual culture, conservation and museology." A quick browse of the available papers shows that they do indeed live up to this claim. For example, a visitor can read an article on the difficulties of conserving the work of Joseph Beuys, an artist who often used organic materials that are bound to decompose (such as fat and wool), but who made contradictory statements regarding his willingness to allow his work to self-destruct. In the same issue (Autumn 2005) a visitor can read a much more traditional article researching the history and attribution of Thomas Gainsborough's 1781 portrait of Marie Jean Augustin Vestris, which passed from the hands of private collectors to the National Gallery in 1888, and has belonged to the Tate since 1955.