A proposed tunnel to drain a gravel channel of water to be used for hydraulic mining. "Present diggings" are shown in vicinity of the Malakoff Diggings, now a State Park, illustrating vividly this destructive method of mining for gold. Verso is a spread sheet. Submap: [cross] section through Bloomfield Tunnel. Prime meridian: GM. Relief: no. Graphic Scale: Feet. Projection: Plane. Printing Process: Lithography. Verso Text: Tabular statement for ... Bloomfield Tunnel. MS note: 436186.
1 map ; printed col. ; 22 x 39 cm., sheet 43 x 66 cm.
North Bloomfield Gravel Mining Company--Maps Gold mines and mining--California--Nevada County--Maps Mining claims--California--Nevada County--Maps Real property--California--Nevada County--Maps Nevada County (Calif.)--Maps
North America United States California Nevada (County) W 120°53'59"/N 39°22'05"
Huntington Rare Book Maps Maps, Huntington Digital Library