SULPHUR,  PYRITE,  AND  ALUM. 
The  following  paper,  by  Mr.  G.  I.  Adams,  contains  a  description  of 
the  sulphur  mines  of  northwestern  Nevada,  and  in  this  connection 
there  is  also  presented  a  brief  report  by  Mr.  J.  E.  Spurr,  on  a  deposit 
of  sulphur  and  alum  near  Silver  Peak,  Nev. 
THE  RABBIT  HOLE  SULPHUR  MINES  NEAR  HUMBOLDT 
HOUSE,  NEV. 
By  George  I.  Adams. 
Location  of  the  mines. — The  Rabbit  Hole  sulphur  mines  are  in 
northwestern  Nevada,  at  the  western  base  of  the  Kamma  Mountains, 
on  the  border  of  Black  Rock  Desert,  about  35  miles  northwest  of 
Humboldt  House,  a  station  on  the  Southern  Pacific  Railroad,  from 
which  they  may  be  reached  by  a  wagon  road  having  moderately  easy 
grades.  The  mines  derive  their  name  from  Rabbit  Hole  Springs,  near 
which  they  are  located. 
Economic  development. — The  geology  of  this  portion  of  Nevada  is 
described  in  the  reports  of  the  Geological  Exploration  of  the  Fortieth 
Parallel,  but  at  the  time  those  reports  were  made  the  sulphur  mines 
had  not  been  developed.  The  sulphur  deposit  was  discovered  about 
thirty -five  years  ago  by  an  Indian,  who  sold  his  claim  for  a  horse  and 
saddle,  which  he  never  received.  It  was  first  worked  in  1874  in  a  small 
way.  Mr.  I.  C.  Russell  visited  the  locality  and  described  the  occur- 
rence of  sulphur  in  the  Transactions  of  the  New  York  Academy  of 
Sciences  for  1882  (p.  173).  He  reported  that  at  that  time  the  mines 
were  producing  about  0  tons  of  sulphur  a  day.  They  are  now  worked 
by  the  Nevada  Sulphur  Company,  of  San  Francisco,  which  assumed 
control  of  them  in  1900.  The  equipment  consists  of  two  retorts, 
which  receive  about  2i  tons  at  each  charge. 
The  rock  containing  the  sulphur  is  assorted  at  the  mines  and  pits, 
and  at  the  mill  is  dumped  over  a  "  grizzly,"  from  which  it  goes  into 
the  retorts.  After  the  retorts  are  charged,  they  are  closed,  and  live 
steam  is  turned  into  them  at  a  pressure  of  about  70  pounds  to  the 
square  inch,  but  as  the  sulphur  melts  the  pressure  is  decreased  some- 
what— to  about  60  or  even  50  pounds.  The  melted  sulphur  sinks 
through  a  grate  into  the  kettle-like  bottom  of  the  retort.  From  the 
Bull.  225—04 32  497 
