110  BIBLIOGRAPHY    OF    NORTH    AMERICAN    GEOLOGY 
Eckel  (Edwin  C.)—  Continued. 
15.  The  Dahlonega  gold  district  ©f  Georgia. 
Eng.  &  Mg.  Jour.,  vol.  75,  pp.  219-220,  1903. 
Describes  the  general  geology  of  the  region,  and  the  character  and  occurrence  of  the  ore 
deposits. 
16.  Gold  and  pyrite  deposits  of  the  Dahlonega  district,  Georgia. 
U.  S.  Geol.  Surv.,  Bull.  no.  213,  pp.  57-63,  1903;  Mines  &  Minerals,  vol.  23,  pp.  493-494,  1903. 
Gives  a  general  account  of  the  geology  of  the  region  and  the  character  and  occurrence  of  gold 
and  pyrite  deposits. 
17.  Utilization  of  iron  and  steel  slags. 
U.  S.  Geol.  Surv.,  Bull.  no.  213,  pp.  221-231,  1903. 
18.  Stoneware  and  brick  clays  of  western  Tennessee  and  northwestern  Mississippi. 
U.  S.Geol.  Surv.,  Bull.  no.  213,  pp.  382-391,  1903. 
Describes  occurrence,  character,  and  utilization  of  clay  deposits  in  this  region. 
19.  Salt  and  gypsum  deposits  of  southwestern  Virginia. 
U.  S.  Geol.  Surv.,  Bull.  no.  213,  pp.  406-416,  1903. 
Describes  briefly  the  stratigraphy  and  geologic  structure  of  the  region,  and  the  occurrence  of 
salt  and  gypsum  deposits  and  their  development. 
20.  The  white  phosphates  of  Decatur  County,  Tenn. 
U.  S.  Geol.  Surv.,  Bull.  no.  213,  pp.  424-425,  1903. 
Describes  occurrence  of  phosphate  deposits  in  this  area. 
21.  Dahlonega  mining  district,  Georgia. 
Abstract:  Science,  new  ser.,  vol.  17,  p.  793,  1903. 
Gives  observations  upon  the  geology  of  the  region. 
22.  Gypsum  deposits  in  New  York. 
U.  S.  Geol.  Surv.,  Bull.  no.  223,  pp.  33-35,  1  pi.,  2  figs.,  1904. 
Describes  economic  development  and  geologic  relations  of  the  gypsum  deposits  in  the  Salina 
group. 
23.  Gypsum  deposits  in  Virginia. 
U.  S.  Geol.  Surv.,  Bull.  no.  223,  pp. 36-37,  1  pi.,  1  fig.,  1904. 
Describes  economic  development  and  geologic  relations  of  gypsum  beds  occurring  in  Carbon- 
iferous strata. 
24.  The  slate  deposits  of  California  and  Utah. 
U.  S.  Geol.  Surv.,  Bull.  no.  225,  pp.  417-422,  1904. 
Describes  the  occurrence  and  character  of  slate  deposits  in   Eldorado  County,  California,  and 
near  Provo,  Utah. 
25.  Cement-rock  deposits  of  the  Lehigh  district  of  Pennsylvania  and  New  Jersey. 
U.  S.  Geol.  Surv.,  Bull.  no.  225,  pp.  448-455,  1904. 
Describes  location  and  general  geology  of  the  district,  the  stratigraphic  position  and  charac- 
ter of  the  cement  rock,  methods  of  manufacturing,  and  character  of  the  product. 
26.  The  salt  industry  in  Utah  and  California. 
U.  S.  Geol.  Surv.,  Bull.  no.  225,  pp.  488-495,  1904. 
Describes  character  and  source  of  materials  used  and  methods  of  manufacture  employed. 
27.  On  a  California  roofing  slate  of  igneous  origin. 
Jour.  Geol.,  vol.  12,  pp.  15-24,  1904. 
Describes  occurrence  and  character  of  slate  deposits  in  California  and  discusses  their  origin. 
28.  On  the  chemical  composition  of  American  shales  and  roofing  slates. 
Jour.  Geol.,  vol.  12,  pp.  25-29,  1904. 
29.  The  nonmetallic  mineral  products  of  the  United  States. 
Mg.  Mag.,  vol.  10,  pp.  167-174,  1  pi.,  1904. 
Cqntains  notes  on  the  occurrence  of  nonmetallic  mineral  products. 
30.  Brown  hematite  deposits  of  eastern  New  York  and  western  New  England. 
Eng.  &  Mg.  Jour.,  vol.  78,  pp.  432-434,  6  figs.,  1904. 
Describes  the  general  geology  of  the  region  and  the  character  and  occurrence  of  the  iron 
ores  and  discusses  their  origin. 
