Calomel  in  Japan.  235 
owing  to  any  reduction  to  metal.  European  calomel  suffers  a  simi- 
lar change.  Keifun  is  free  from  corrosive  sublimate  and  from 
metallic  mercury. 
Hanbury  found  selenite  in  Chinese  calomel,  and  Geerts  found 
calomel  of  this  form  generally  adulterated  with  selenite  and  mica  ;  but 
whether  what  he  examined  was  ever  Japanese  and  not  always 
imported  Chinese  calomel  he  does  not  show.  I  have  found  keifun 
as  it  came  direct  from  Ise  quite  free  from  adulteration,  and  have  not 
met  with  any  adulterated. 
Of  the  Materials  Used  in  Making  Calomel  in  Ise,  Japan. — The 
materials  for  making  Japanese  calomel  are :  mercury,  an  arenaceous, 
red  clayey  earth,  bay-salt,  bittern  or  salt  mothers,  and  air.  The 
mercury  is  imported  from  Europe,  but  in  old  times  it  is  said  to 
have  heen  found  in  the  neighborhood  of  Ise,  as  cinnabar. 
The  earth,  called  mitsuchi  ("seed-earth"),  is  all  taken  from  a 
neighboring  hill,  Shunakayama,  and,  according  to  Mr.  Kokubu, 
many  other  clays  have  been  tried  in  place  of  it,  always  with  bad 
results.  It  is  of  a  rather  light-brown  red  color,  which  changes  to  a 
duller  and  somewhat  brown  red  on  drying  and  gently  heating  the 
earth,  and  to  a  light  ordinary  brick  red  by  a  strong  heat.  As  mined, 
the  earth  is  seen  to  consist  largely  of  colorless  quartz  grains 
Besides  the  quartz  a  very  little  biotite  is  seen  sparkling  through  it. 
The  fresh,  damp  earth  does  not  form  a  compact  mass,  but  a  slightly 
cohering  aggregate  of  damp  crumbs.  This  texture  appears  to  be 
due  to  the  earth  being  a  mass  of  quartz  in  small  grains,  from  the  size 
of  a  hempseed  down  to  that  of  impalpable  particles  held  together  by 
plastic  clay.  For  use,  that  which  does  not  contain  coarse  quartz 
grains  too  abundantly  is  selected,  and  is  made  into  briquettes  and 
moderately  baked  on  the  hearth  of  the  fire-place  under  the  calomel 
pots.  These  briquettes  are  then  as  light  and  porous  as  the  prepared 
porous  clay  used  in  Fletcher's  gas-furnaces.  The  raw  earth,  air-dried, 
is  readily  rubbed  into  its  constituents  by  the  fingers ;  and  the  baked 
briquettes  very  easily  and  rapidly  reduced  to  a  soft  powder,  quartz 
grains  and  all,  in  the  agate  mortar.  The  larger  grains  of  quartz  in 
the  raw  earth  are  also  very  brittle.  I  have  treated  thus  fully  of  the 
mechanical  characters  of  the  earth,  because  probably  much  of  its 
efficiency  is  due  to  them  ;  but  its  chemical  character  also  calls  for 
notice.  As  baked  ready  for  use,  it  contains  in  the  thoroughly  air- 
dry  condition  still  5  per  cent,  and  more  of  water.    Before  ignition 
Am.  Jour.  Pharm. 
May,  1894. 
