192  Field  Columbian  Museum — Reports,  Vol.  i. 
installation,  which  enables  the  visitor  to  study  accurately  and  rapidly 
the  different  steps  of  the  processes.  Similar  collections  illustrating 
the  extraction  of  copper  have  been  placed  in  Hall  79.  The  processes 
so  represented  include  the  Friedrichshutte  and  Lantenthalshutte  proc- 
esses for  refining  lead  and  silver ;  the  blast  furnace  process  for  the 
extraction  of  lead;  the  Argo,  Colorado,  smelting  process  for  extracting 
gold,  silver  and  copper  ;  the  Friedrichshutte  reverberatory  process 
for  extracting  lead  and  silver,  the  blast  furnace  process  for  the 
extraction  of  copper,  and  the  reverberatory  furnace  or  Swansea  proc- 
ess for  the  extraction  of  copper.  In  Hall  79  an  entire  re-arrange- 
ment has  been  made  of  the  iron,  nickel,  arsenic  and  other  ores,  so 
that  now  they  present  a  more  logical  order  than  heretofore  and  their 
study  is  facilitated.  The  cases  in  Halls  72  and  79  have  been  lined  and 
painted  to  give  a  better  background  for  the  specimens  and  preserve 
them  from  dust.  In  Hall  72  the  large  collection  of  silver  ores  made 
by  the  Curator  in  Mexico  has  been  installed  so  that  a  very  satis- 
factory representation  of  these  ores  can  be  seen.  The  specimens 
of  gold  and  silver  alloys,  which  had  tarnished  badly,  have  been 
reburnished,  through  the  kindness  of  Messrs.  Tiffany  &  Co.,  of  New 
York.  In  Hall  72,  devoted  to  the  metallurgy  of  iron,  changes 
involving  a  large  amount  of  time  and  labor  have  been  made,  but  the 
improved  appearance  of  the  hall  amply  compensates  for  the  expendi- 
ture. The  large,  heavy  objects  having  little  significance  have  been 
removed,  and  their  places  have  been  supplied  by  cased  models  of 
rolling  mills,  hot  blast  stoves,  etc.,  and  a  case  of  specimens  illustrat- 
ing the  manufacture  of  different  grades  of  pig  iron.  The  large  collec- 
tion of  test  specimens  illustrating  the  tensile  strength  of  various 
grades  of  iron  has  been  fully  and  accurately  labeled,  and  the  same  is 
true  of  all  the  objects  shown  in  the  hall.  In  its  present  form  the  hall 
attracts  much  attention  and  is  a  place  where  valuable  information 
regarding  the  metallurgy  of  iron  can  be  obtained. 
The  Curator  of  the  Department  of  Botany  has  added  to  the 
herbarium  during  the  year,  six  more  cases  containing  about  4,000 
species,  and  in  completing  the  installation  of  economic  material  four 
large  cases  have  been  installed  on  the  transept  of  the  west  gallery. 
Considerable  work  has  also  been  performed  in  caring  for  the  speci- 
mens in  the  old,  and  not  very  desirable  cases  in  different  parts  of 
the  department  and  in  installing,  according  to  the  plan  described  at 
some  length  elsewhere,  that  portion  of  the  North  American  Forestry 
collection  already  received.  A  force  of  workmen  has  also  been  engaged 
in  the  workshop  on  Jefferson  avenue,  at  different  times  during  the 
year,  preparing  woods  for  this  collection. 
