76  CONTRIBUTIONS    TO    ECONOMIC    GEOLOGY,  1900,  PART    T. 
That  these  upper  Snake  River  gravels  contain  gold  has  been  know 
for  some  time,  and  as  early  as  1S62  prospectors  were  trying  to  extract 
the  shining  colors  or  gold  flakes  from  the  coarse  gravels  and  fine  san< 
along  the  stream.  Some  of  the  first  workings  on  the  Snake  above  tin 
(hand  Canyon  were  in  Jackson  Hole,  north  of  Gros  Ventre  River. 
These  early  discoveries  are  described  by  Frank  H.  Bradley, a  in  his 
report  on  the  Snake  River  expedition  in  1872,  as  follows: 
A  considerable  excitement  was  stirred  up,  a  few  years  since,  by  reported  discoverie 
of  placer  gold  in  large  quantities  on  the  upper  Snake,  and  many  prospectors  visited  thi 
region.  A  small  hydraulic  operation  was  und<  rtaken  near  this  point ;  l>nt  the  gold  wa 
too  line  and  in  too  small  quantities  to  paw  and  the  whole  region  was  entirely  abandone 
after  a  few  monl as.  The  e.'arse  gold,  found  on  the  lower  part  of  the  Snake,  appears  i< 
have  entered  the  riv<  r  below  the  canyon,  which  is  still  to  the  southward  of  us. 
In  L878  Orestes  St.  John6  found  on  the  terraced  interval  along 
Snake  River  in  the  vicinity  of  Bailey  Creek  indications  of  old  placer 
workings  that  had  been  opened  in  1870  by  a  party  of  miners  assc 
ciated  with  Jeff  Stahtiford.  The  enterprise  was,  however,  interfere* 
with  by  the  Indians  and  organized  mining  operations  were  discon- 
tinued, hi  reeent  years  considerable  prospecting  has  been  done  alon| 
Snake  and  Hoback  rivers,  but  very  little  real  development  work  has 
been  carried  on.  (Maims  have  been  located  and  staked  out  on  th< 
gravel  ten-aces  along  the  greater  portion  of  Snake  River  and  alonj 
Hoback  River  below  its  canyon,  but  only  enough  work  has  been  done 
to  hold  t  he  claims. 
The   placer-gold   deposits   along  Snake    River  may  be 'classed   as 
stream   placers  and   bench   placers.     The  stream   placers  consist   o 
the  deposits  of  bowlders,  gravels,  and  sand  that  form  bars,  banks,  (ills, 
and   shoal>   in    or  adjacent    to   the  streams,    filling  the  channels   aiu 
forming  the  stream  beds.      Many  of  the  bars,  banks,  and  (ills  are  only 
temporary  and   vary  more  or  less  during  every   heavy  storm.     The 
bench   placers  are   located   in   the  old   stream   deposits,   which   are  a 
present    represented   by  the  terrace  remnants  that  mark  the  forme 
level  of  the  stream  at  a  considerable  elevat  ion  above  the  present  rive 
bed.      None   of    the   stream-placer  deposits   within    the    area    are   a 
present  worked  and  only  in  two  localities  are  the  bench  placers  minc( 
systematically.     These  are  on  Andrew  J.  Davis's  claim  on  the  east  ban! 
of  the  river,  north  of  the  mouth  of  Bailey  Creek,  and  on  Hoffer  & 
Rosencrans's  claim  at  Pine  Bar,  on  the  south  side  of  Snake  River  at 
the  mouth  of  Pine  Creek,  1  \  miles  below  the  mouth  of  Bailey  Creek. 
(See  map,  PI.  I.) 
a  Sixth  Ann.  Kept.  U.  S.  Geol.  Survey  Terr.,  1873,  p.  266. 
6  Twelfth  Ann.  Kept.  (J.  S.  <;«'<>!.  and  Geog.  Survey  Terr.,  pt.  1,  1883,  p.  196. 
