APPROXIMATELY LOCATED IN OR AROUND THE BRISTOL MINING DISTRICT; PROVIDES EXPLANATION; APPROX. SCALE 1 INCH = 650 FEET; BASE AFTER U.S. DEPT. OF AGRI. S.C.S. AERIAL PHOTO BPD 74-70 (UNADJUSTED) ; AUTHOR: CALLAHAN, W.S.; COURTRIGHT, J.H.; DAWSON, G.A.; FULTON, R.B.; HARDIE, B.S.; KINNEBERG, A.H.; KINNEBERG, J.C.; KITTLE, O.A.; WHEELER, H.E.; ROBERTS, F.B.