Block book showing the assessed district for the opening and extension of Potrero Avenue from New Channel Street to 9th Street, and from 25th Street to the county line, and for the opening and extension of 10th Street and Brannan Street to Potrero Avenue. The block book was prepared for the Honourable Board of Commissioners (Chairman E R Swain, Daniel Sullivan, Max Goldberg, Attorney A Ruef, and Secretary C J Hutchins) by M M O'Shaughnessy C E. The drawings are at a scale of 60 feet to 1 inch. Each drawing measures 94 x 78 cm.