4^2 
The  International  Exposition. 
{Am.  Tour.  Pharra . 
Sept.,' 1876. 
xegard  this  as  the  most  interesting  and  instructive  exhibition  of  the  chemistry  of 
opium,  on  account  of  the  variety  of  compounds,  the  number  of  rare  preparations 
-and  the  results  of  original  investigations. 
More  limited  in  the  countries  of  production  is  camphor,  which  is  furnished  by 
the  laurel  Camphora  officinarum,  Bauh.,  a  stately  tree  of  Japan  and  the  eastern 
portion  of  Asia,  where  it  is  obtained  by  subjecting  the  cut  branches  and  wood  to 
a  crude  distillation  in  the  presence  of  water;  after  draining  it  in  vessels  having  a 
perforated  bottom,  it  is  met  with  in  the  market  as  Chinese  and  Japanese  camphor, 
which  varieties  are  exhibited  in  their  proper  departments.  The  former,  or  Formosa 
camphor,  is  usually  of  a  light-brown  or  grey  color,  the  latter  is  nearly  white,  or  some- 
what pinkish,  and  both  occur  in  their  crude  state  in  the  form  of  small  grains.  "The  re- 
fining of  the  crude  article  appears  to  be  carried  on  in  Europe  still  in  peculiar-shaped 
glass  flasks,  which  require  to  be  broken  in  order  to  obtain  the  cake  of  sublimed 
camphor.  Of  late  years  the  refining  of  camphor  has  become  quite  an  industry  in 
the  United  States,  where  it  is  effected  in  vessels  constructed  for  the  purpose,  having 
;a  movable  lid,  upon  which  the  sublimate  condenses;  with  this  arrangement  the  ex- 
pense of  a  glass  vessel  for  each  cake  is  saved. 
Crude  camphor  is  exhibited  by  China  and  Japan  as  one  of  their  staple  articles, 
and  in  the  department  of  the  latter  country  is  also  found  some  refined  camphor  in 
large  fragments,  apparently  broken  from  larger  cakes.  Circular  cakes  of  the  re- 
ined article,  with  the  accustomed  circular  hole  in  the  center,  are  exhibited  by  Chas. 
Pfizer  &  Co.,  of  New  York,  and  Kurlbaum  &  Co.,  of  Philadelphia,  the  last-named 
ifirm  collecting  also  the  volatile  oil  with  which  the  crude  camphor  is  always  more 
or  less  impregnated,  and  which  is  lost  in  the  old  method  of  purification  ;  like  the 
Formosa  oil  of  camphor  with  which  it  is  identical,  it  contains  variable  quantities  of 
•  camphor  in  solution. 
Camphor,  as  is  well  known,  is  extensively  employed  for  protecting  clothes  from 
•  the  ravages  of  moths  ;  the  crystalline  cakes,  in  which  it  is  usually  met  with,  con- 
tain many  fissures,  from  which  the  volatilization  of  the  camphor  proceeds,  the  same 
as  from  the  surface.  It  is  obvious,  that  with  a  decrease  of  the  entire  space  presented 
to  the  air,  the  rapidity  of  evaporation  must  necessarily  be  lessened,  while  its  effec- 
'tiveness  must  remain  the  same  if,  through  the  slower  evaporation,  the  confined  at- 
mosphere may  still  be  kept  saturated  with  camphor.  This  idea  is  carried  out  in 
«the  compressed  camphor,  manufactured  and  exhibited  by  W.  F.  Simes  &  Son.  This 
/firm  distil  crude  Japanese  camphor  slowly  from  a  suitable  retort,  and  carry  the 
^vapors  into  a  large  chamber,  where  it  condenses  in  the  form  of  a  very  fine  crystal- 
iiin«  powder,  which  is  afterwards  compressed  by  hydraulic  pressure  into  rectangular 
blocks  of  a  definite  weight.  These  blocks  may  also  be  made  directly  from  the 
crude  camphor,  and  then  contain  also  the  small  percentage  of  impurities  naturally 
found  therein. 
_  Among  the  chemical  derivatives  of  camphor  we  notice  crystallized  camphoric  acid, 
in  the  interesting  and  instructive  exhibit  of  H.  TrommsdorfF,  Erfurt,  and  monobro- 
mated camphor,  by  most  of  the  manufacturers  of  medicinal  chemicals  of  the  United 
States,  Germany  and  some  other  countries.  If  we  are  permitted  to  judge  from  the 
number  of  exhibitors  in  the  various  departments,  and  from  the  quantities  exhibited,  this 
compound  has  everywhere  rapidly  gained  the  confidence  of  physicians,  and  become  an 
