FOR    THE    YEARS    1901-1905,    INCLUSIVE.  99 
Derr  (Homer  Munro). 
1.  A  method  of  petrographic  analysis  based  upon  chromatic  interference  with  thin 
sections  of  doubly-refracting  crystals  in  parallel  polarized  light.     Thesis  pre- 
sented to  the  Faculty  of   Philosophy  of  the   University   of  Pennsylvania   in 
partial  fulfillment  of  the  requirements  for  the  degree  of  Doctor  of  Philosophy. 
The  Randal  Morgan  Laboratory  of  Physics,  1903.    21  pp.,  2  pis.,  4  figs. 
Dickinson  (Harold  T. ). 
1.  Quarries  of  bluestone  and  other  sandstones  in  the  upper  Devonian  of  New  York 
State. 
N.  Y.  State  Museum,  Bull.  no.  61,  112  pp.,  20  pis.,  1903. 
Describes  the  character,  occurrence,  and  quarrying. 
Dickson  (Charles  William). 
1.  Note  on  the  condition  of  nickel  in  nickeliferous  pyrrhotite  from  Sudbury  [Ontario] . 
Eng.  &  Mg.  Jour.,  vol.  73,  p.  660,  1902. 
Contains  notes  on  the  concentration  of  some  of  these  ores. 
2.  The  concentration  of  barium  in  limestone. 
School  of  Mines  Quart.,  vol.  23,  pp.  366-370,  1902. 
3.  Note   on   the   condition  of   platinum   in   the   nickel-coppe  •  ores  from    Sudbury 
[Ontario] . 
Am.  Jour.  Sci.,  4th  ser.,  vol.  15,  pp.  137-139,  1903. 
Describes  occurrence  and  crystallographic  characters. 
4.  The  ore  deposits  of  Sudbury,  Ontario. 
Columbia  Univ.,  Contr.  from  Geol.  Dept.,  vol.  11,  no.  91,  65  pp.,  26  figs.,  190S;  Am.  Inst.  Mg. 
Engrs.,  Trans.,  vol.  34,  pp.  3-67,  26  figs.,  1904. 
Contains  a  discussion  of  the  origin  of  the  Sudbury  nickeliferous  ores.    Includes  a  bibliography 
of  the  subject. 
5.  The  distribution  of  the  platinum  metals  in  other  sources  than  placers. 
Can.  Mg.  Inst.,  Jour.,  vol.  8,  pp.  192-214,  1905. 
Describes  the  various  occurrences  of  platinum. 
Diehl  (O.  C). 
1.  Gypsum. 
Mich.  Miner,  vol.  6,  no.  6,  pp.  21-24,  1904. 
Describes  the  occurrence  of  gypsum  in  Michigan  and  Utah. 
Diller  (Joseph  Silas). 
1.  The  Klamath  Mountains. 
Mazama,  vol.  1,  no.  1,  pp.  104-108,  1896. 
Describes  briefly  the  geologic  history  of  the  Klamath  Mountains  region. 
2.  The  geology  of  Crater  Lake. 
Mazama,  vol.  1,  no.  2,  pp.  161-170,  4  pis.,  1897. 
Describes  geologic  structure  and  history  of  Crater  Lake  on  Mount  Mazama,  Oregon. 
3.  Geomorphogeny  cl  the  Klamath  Mountains  [California-Oregon]. 
Abstracts:  Geol.  Soc.  Am.,  Bull.,  vol.  12,  p.  461,  1901;  Science,  new  ser.,  vol.  13,  p.  97,  1901. 
4.  Coos  Bay  folio,  Oregon. 
U.  S.  Geol.  Surv.,  Geol.  Atlas  of  U.  S.,  folio  no.  73,  1901. 
Describes  the  topographic  features,  the  character,  and  the  occurrence  of  the  Cretaceous, 
Eocene,  Neocene,  and  Pleistocene  deposits  and  igneous  rocks,  and  the  occurrence  of  coal 
and  gold. 
5.  The  copper  region  of  northern  California. 
Eng.  &  Mg.  Jour.,  vol.  73,  pp.  857-858,  1  fig.,  1902;  Science,  new  ser.,  vol.  15,  p.  823,  1902. 
Describes  the  occurrence  of  auriferous  quartz  veins  and  copper  deposits  of  the  region. 
6.  Copper  in  northern  California. 
Mg.  &  Sci.  Pres.,  vol.  85,  pp.  62,  72,  1902. 
Discusses  the  geologic  occurrence  of  copper  ores. 
