284  BIBLIOGRAPHY    OF    NORTH    AMERICAN    GEOLOGY 
Richardson  (George  Burr) — Continued. 
4.  Report  of  a  reconnaissance  in  trans-Pecos  Texas,  north  of  the  Texas  and  Pacific 
Railway. 
Tex.  Univ.,  Min.  Surv.,  Bull.  no.  9,  119  pp.,  11  pis.,  4  figs.,  1904. 
Describes  the  topography,  the  character,  occurrence,  and  geologic  relations  of  pre-Cambrian. 
Cambrian,  Ordovician,  Silurian,  Carboniferous,  Triassic,  Jurassic,  Cretaceous,  and  Quater- 
nary deposits,  the  mineral  resources,  and  underground  water  supply  of  the  region. 
5.  Stratigraphic   sequence   in   trans-Pecos   Texas,   north  of  the   Texas  and  Pacific 
Railway. 
Abstract:  Science,  new  ser.,  vol.  19,  pp.  794-795.  1904. 
6.  Natural  gas  near  Salt  Lake  City,  Utah. 
U.  S.  Geol.  Surv.,  Bull.  no.  260,  pp.  480-483,  1905. 
Describes  the  occurrence  and  character  of  natural  gas  near  Salt  Lake  City,  Utah. 
7.  Salt,  gypsum,  and  petroleum  in  trans-Pecos  Texas. 
U.  S.  Geol.  Surv.,  Bull.  no.  260,  pp.  573-585,  1  fig.,  1905. 
Describes  briefly  the  topography  and  stratigraphy  of  the  region,  and  the  occurrence  of  salt, 
petroleum,  and  gypsum. 
8.  Native  sulphur  in  El  Paso  County,  Tex. 
I\  S.  Geol.  Surv.,  Bull.  no.  260,  pp.  589-592,  1905. 
Describes  the  occurrence  of  sulphur. 
Rickard  (Edgar). 
1.  Tin  deposits  of  the  York  region,  Alaska. 
Eng.  &  Mg.  Jour.,  vol.  75,  pp.  30-31,  1903. 
Describes  the  geology  of  the  region  and  the  occurrence  of  tin. 
Rickard  (Forbes). 
1.  Notes  on  Nome,  and  the  outlook  for  vein  mining  in  that  district  [Alaska]. 
Eng.  and  Mg.  Jour.,  vol.  71,  pp.,  275-276,  1  fig.,  1901. 
Contains  notes  on  the  geology  of  the  region  and  the  occurrence  of  gold. 
2.  Copper  deposits  in  Sinaloa  and  southern  Sonora  [Mexico]. 
Eng.  &  Mg.  Jour.,  vol.  78,  pp.  97-98,  4  figs.,  1904. 
Describes  the  occurrence,  geologic  relations,  and  economic  development  of  copper-ore  depos 
its  in  this  part  of  Mexico. 
3.  Notes  on  tungsten  deposits  in  Arizona. 
Eng.  &  Mg.  Jour.,  vol.  78,  pp.  263-265,  2  figs.,  1904. 
Describes  the  general  geology  of  the  Little  Dragoon  mountains  in  Arizona,  and  the  geologic 
relations,  occurrence,  character,  and  mining  of  the  deposits  of  tungsten  ores. 
Rickard  (T.  A. ) 
1.  The  Cripple  Creek  volcano  [Colorado]. 
Am.  Inst.  Mg.  Engrs.,  Trans.,  vol.  30,  pp.  367-403,  2  figs.,  1901. 
Gives  an  account  of  the  various  stages  of  eruption  in  this  volcano  and  compares  it  with  vol- 
canos  in  other  regions. 
2.  The  telluride  ores  of  Cripple  Creek  [Colorado]  and  Kalgoorlie  [Australia]. 
Am.  Inst.  Mg.  Engrs.,  Trans.,  vol.  30,  pp.  708-718,  1901. 
Describes  the  characteristics  of  the  ores  of  these  regions. 
3.  The  formation  of  bonanzas  in  the  upper  portions  of  gold-veins. 
Am.  Inst.  Mg.  Engrs.,  Trans.,  vol.  31,  pp.  198-220,  1902. 
Discusses  enrichment  by  concentration  through  the  action  of  underground  water  by  solution 
and  precipitation,  and  the  distribution  of  ore-bonanzas  in  Australia,  Colorado,  California, 
and  New  Zealand. 
4.  Recent  progress  in  the  study  of  ore  deposits. 
Eng.  &  Mg.  Jour.,  vol.  73,  pp.  106-107,  1902. 
5.  The  Geological  Survey  and  the  western  mines. 
Eng.  &  Mg.  Jour.,  vol.  74,  p.  5,  1902. 
6.  An  example  of  the  localization  of  rich  ore. 
Eng.  &  Mg.  Jour.,  vol.  74,  pp.  847-850.  6  figs..  1902. 
