I4o  Making  Soya-Bean  Oil  in  Manchuria.  {AY'e&0uIww?: 
is  produced,  and  this  is  said  to  be  preferred  to  cake  for  fertilizer, 
as  it  requires  no  breaking  before  it  is  used  on  fields.  The  oil,  how- 
ever, is  said  to  sell  for  less  than  that  produced  by  the  "  expression 
process,"  as  it  is  difficult  to  remove  all  traces  of  benzine  from  the 
oil.  The  term  soya-bean  oil  is  generally  understood  to  mean  ex- 
pressed oil. 
Fifty-odd  mills,  large  and  small,  are  using  the  expression  proc- 
ess at  Dairen.  Usually  they  are  open  to  inspection  upon  proper  in- 
troduction. Vertical  presses  of  four  columns  of  about  25  cakes  per 
column  are  used,  some  mills  having  double  presses — presses  on  two 
floors,  one  directly  above  the  other  and  built  as  one  machine,  with 
the  power  applied  at  the  same  time  in  one  operation.  It  is  customary 
to  work  these  presses  by  hydraulic  power.  They  are  displacing  the 
old  hand-power  screw  press. 
When  the  beans  are  received  at  the  mill  they  are  generally  frozen 
or  very  near  it.  After  being  sifted  to  remove  such  matters  as  stones, 
dirt,  etc.,  they  are  kept  for  several  days  in  a  warm  room,  where  they 
are  turned  over  with  shovels  and  thoroughly  mixed  from  time  to 
time.  No  magnetic  cleaning  is  done  at  any  of  the  mills  except  the 
chemical  mill,  which  additionally  uses  this  method.  No  particular 
temperature  is  aimed  at,  the  object  being  simply  to  warm  the  beans 
so  that  the  oil  will  be  more  easily  freed.  After  they  have  been 
warmed  for  several  days  they  are  conveyed  to  the  top  of  the  crush- 
ers and  run  down  through  a  series  of  cylindrical,  smooth,  or  nearly 
smooth,  iron  rollers,  which  roll,  not  grind  them.  They  emerge  as 
disks,  the  size  and  shape  of  a  dime.  They  fall  from  the  rollers  into 
a  trough  in  which  a  screw  conveyor  is  turning,  and  conveys  them  to 
the  pressing  floors,  where  they  fall  into  bins. 
The  press  gangs  have  ready  squares  of  gunny-bag  cloth,  each  of 
which  holds  a  sufficient  quantity  of  rolled  beans  to  make  a  cake. 
The  required  quantity  is  scooped  up  and  put  into  the  cloth,  which 
is  then  carried  to  the  steam  box.  The  cloth  is  spread  out  over  the 
steam  box,  with  the  beans  a  couple  of  inches  deep,  and  the  steam  is 
turned  on  and  allowed  to  flow  up  through  the  mass  for  two  or  three 
minutes.  The  steam  is  not  under  pressure  when  applied,  but  escapes 
into  the  room,  and  no  particular  degree  of  temperature  is  aimed  at, 
a  thorough  steaming  being  all  that  is  desired,  with  the  warming  at- 
tained at  the  same  time. 
Meanwhile  several  more  coolies,  who  work  naked  or  with  a  loin 
cloth  and  sweatband  only,  have  prepared  the  form.    This  consists 
