218  BIBLIOGRAPHY    OF    NORTH    AMERICAN    GEOLOGY 
Lefifmann  ( Henry) . 
I .  The  microscopic  structure  of  building  stones. 
Engrs.  Club  Phila.,  Proc,  vol.  22.  pp.  327-342,  illus.,  1905. 
Leith  (Charles  Kenneth). 
1.  Summaries  of  current  North  American  pre-Cambrian  literature. 
.lour.  Geol.,  vol.  9,  pp.  79-87  and  411-458,  1901. 
2.  Geology  of  the  Mesabi  Iron  region. 
Eng.  &  Mg.  Jour.,  vol.  73,  p.  277,  1902;  Science,  new  ser.,  vol.  15,  p.  351,  1902. 
Abstract  of  paper  read  before  the  Geological  Society  c£  Washington.    Discusses  the  strati- 
graphic  geology  and  the  origin  of  the  ores. 
3.  Pre-Cambrian  summaries  for  1901. 
.lour.  Geol.,  vol.  10,  pp.  891-913,  1902. 
4.  The  Mesabi  iron-bearing  district  of  Minnesota. 
U.  S.  Geol.  Surv.,  Mon.,  vol.  43,  316  pp.,  33  pis.,  12  figs.,  1903. 
Describes  geography  and  topography,  gives  a  brief  history  of  the  opening  and  development 
of  the  district,  and  reviews  the  literature  bearing  on  the  geology  of  the  region.  Describes 
the  lithologic  character,  occurrence,  structure,  and  geologic  relations  of  Archean,  Huronian, 
Keweenawan,  Cretaceouss,  and  Quaternary  deposits  and  discusses  the  geologic  history  of  the 
region,  the  correlation  of  the  formations,  the  distribution,  character,  and  geologic  occur 
rence  of  the  iron  ores,  their  petrographic  relations  to  adjacent  rocks  and  origin,  and  the 
developmenl  of  the  mining  industry  of  the  district. 
5.  Geologic  work  in  the  Lake  Superior  iron  district  during  1902. 
I.  S.  Geol.  Surv.,  Bull.  no.  213,  pp.  247-250,  1903. 
Gives  observations  on  the  character  and  occurrence  of  the  iron  ores. 
6.  Moose  Mountain  Iron  Range  [Ontario]. 
out.  Bur.  Mines,  [12th]  Kept., pp.  318-321,  1  fig.,  bin:;. 
Describes  geologic  features  of  the  range  and  discusses  the  origin  of  Hie  ore. 
7.  Summaries  of  pre-Cambrian  literature  for  1902-1903. 
.lour.  Geol.,  vol.  12.  pp.  52-62,  L903. 
s.    A  comparison  of  the  origin  and  development  of  the  iron  ores  of  the  Mesabi  and 
Gogebic  iron  ranges. 
Lake  Sup.  Mg.  Inst..  Proc.  for  1902,  vol.  8,  ,,,,.  7.V8I  [1903]. 
9.  Summaries  of  pre-( 'ami >rian  literature  for  L902-1903. 
Jour.  Geol.,  vol.  12.  pp.  52-62,  L61-176,  L9.04. 
10.  The  Lake  Superior  iron  region  during  1903. 
('.  s.  Geol.  Surv..  Bull.  no.  225,  pp.  215  220,  1904. 
Describes  the  geologic  occurrence  of  the  iron-ore  deposits  in  the  different  districts  of  the  Lake 
Superior  iron  region. 
11.  Iron  ores  in  southern  Utah. 
I".  S.  Geol.  Surv..  Bull.  no.  225.  pp.229-237,  1904. 
Describes  distribution,  geologic  relations,  and  character  of  the  iron  ores  and  discusses  their 
origin. 
12.  Lake  Superior  iron  region  in  L903. 
Mg.  World,  vol.  21.  pp.  198-200,  3  figs.,  1904. 
Includes  observations  on  the  general  geology  and  the  occurrence  and  character  of  the  iron- 
ore  deposits. 
13.  Rock  cleavage. 
I',  s.  Geol.  Surv.,  Bull.  no.  239,  216  pp.,  27  pis.,  L905. 
14.  A  summary  of  Lake  Superior  geology  with  special   reference  to  recent  studies  of 
the  iron-bearing  series. 
Am.  Inst.  Mg.  Engrs.,  Bi-mo.  Bull.  no.  3,  pp.  453-507,  4  figs.,  1905. 
Describes  the  geology  of  the  Lake  Superior  iron-bearing  and  copper-bearing  series  and  the 
occurrence,  relations,  and  origin  of  the  iron  ores. 
15.  Genesis  of  Lake  Superior  iron  ores. 
Econ.  Geol..  vol.  1,  pp.  47-66,  1905. 
