368 
Field  Columbian  Museum — Reports,  Vol.  i. 
prepared  by  Assistant  Curator  Nichols,  illustrating  the  Le  Blanc 
and  ammonia  processes  for  the  manufacture  of  soda  and  the  differ- 
ent products  obtained.  The  graphic  method  of  installation  which 
has  been  described  in  a  previous  report  and  which  has  proved  most 
satisfactory  in  the  representation  of  metallurgical  processes,  has 
here  been  employed  as  well.  Where  liquids  are  exhibited,  the 
cases  being  flat,  a  rectangular  glass  tray,  6x5x1%  inches  in  size,  with 
a  glass  cover,  has  been  employed.  Specially  corrosive  or  poisonous 
liquids  and  gases  are  exhibited  in  sealed  glass  tubes  about  1 
inch  in  diameter  and  9  inches  in  length.  The  collection  of  min- 
eral paints  in  Hall  77,  which  stood  in  a  central  case  obstructing 
the  passageway,  has  been  removed,  with  additions,  to  another  part  of 
the  hall.  A  collection  of  art  tiles  has  also  been  placed  upon  the 
walls  of  this  hall.  In  Hall  71,  devoted  to  petroleum  and  its  prod- 
ucts, the  cases  have  been  repainted  inside  and  out,  the  specimens 
cleaned  and  newly  installed.  The  heavy  iron  label  frames  and 
exposed  jars,  which  were  liable  to  cause  or  to  suffer  injury,  have 
been  removed,  and  all  the  material  in  the  hall  is  now  cased.  Six 
large  ore  specimens  in  Hall  72  have  been  provided  with  individual 
cases.  The  valuable  series  of  iron  and  steel  fractures  shown  in 
Hall  76,  which  were  beginning  to  rust,  has  been  carefully  cleaned.. 
The  cases  containing  the  fractures  have  been  relined  and  repainted 
inside  and  the  sashes  fitted  with  jambs  of  rubber.  With  the  case 
thus  made  air-tight,  by  the  use  of  lime  or  other  drying  ingredient 
it  is  expected  to  keep  the  case  interiors  dry  and  thus  prevent  any 
further  rusting  of  the  fractures.  Some  other  minor  changes  have 
been  made  in  the  casing  in  this  hall.  The  interiors  of  most  of  the 
wall  cases  and  part  of  the  floor  cases  in  Hall  79  have  been  painted 
white,  and  a  large  wall  case  added  to  contain  the  heavy  specimens 
formerly  piled  along  the  south  wall.  About  one-third  of  the  cases 
containing  the  systematic  mineral  collection,  Hall  63,  have  been 
relined,  the  specimens  cleaned  and  reinstalled.  A  stack  of  trays  for 
storage  purposes  has  been  placed  along  the  east  wall  of  Hall  75.  An 
aspirator,  filter-pump  and  air-bath  have  been  added  to  the  equipment 
of  the  laboratory.  The  work-room  of  vertebrate  palaeontology  has 
been  provided  with  stacks  of  storage-trays,  work-tables  and  other  fit- 
tings. New  pasteboard  trays  have  been  supplied  throughout  to  the 
palaeontological  collection  in  Halls  35,  36  and  59.  The  old  trays, 
being  of  inferior  quality,  had  become  much  faded  and  soiled.  The 
new  style  of  tray,  adopted  after  some  experimenting,  was  a  shallow 
tray  covered  with  black  glazed  paper,  except  where  the  specimen  was 
