Envelope reads "Hetch Hetchy Mitchell tunnel cave-in 1-11-31." Photograph shows a manh holding a piece of paper flat on a board for the camera. The man's hand scan be seen clearly, and he wears a ring. The note is on a torn piece of paper, and reades "Hello SF we are all fine and dandy every body feeling fine after that great feed Purdue and gang." This photogrpah was printed in the Oakland Tribune on January 11, 1931 (p14-A) with the caption "Note of Cheer from Entombed Men, After 20 hours of imprisonment in the Mitchell ravine tunnel of the Hetch Hetchy project, 20 entombed workmen sent this 'note of cheer' to rescue workers through a four-inch pipe. the 'feed' referred to was a meal of bologna, salami, bread and coffee, also sent through the pipe as the first food the entombed men had eated since Friday afternoon before they went on shift." On January 10, 1931 a section of the Mitchell Tunnel near Livermore, Alameda County collapsed, trapping 20 workers. The men spent over 20 hours entombed before being rescued on January 11. The cause of the collapse was not immediately clear, but it followed on a July 1930 accident at the same site. The Mitchell Tunnel was part of the Hetch Hetchy project. Information taken from articles in the Oakland Tribune January 11, 1931. For more information about Hetch Hetchy see h99.1.470.