John Garth (1889-1971) Study for Swing Shift unsigned oil on canvas affixed to board 22 x 52in framed 22 3/4 x 52 7/8in Painted circa 1939. Footnotes: Provenance Sale, Butterfield & Butterfield, San Francisco, American and European Paintings and Sculpture, October 8, 1980, lot 308 (as 'Iron Workers'). Property from the Estate of George R. Bobbitt Jr., San Francisco, California. A note from Kathy (nee Garth) Shea, the artist's daughter, dated October 20, 1995, authenticating the work as by John Garth, accompanies the lot. The present work depicting iron workers was an oil study for John Garth's mural Swing Shift created for the Mines, Minerals and Machinery Building at the Golden Gate International Exposition in 1939.