44 
Cotton  Seed  Oil. 
(  Ajd.  Jour.  Pharm 
t    January,  1896. 
means  of  steam  filters.  The  alkali  remaining  in  the  oil  is  neutral- 
ized by  repeated  washing  with  cold  water,  containing  a  small  quan- 
tity of  an  acid.  When  the  oil  becomes  neutral  to  litmus  paper,  it 
is  run  into  large  tanks.  After  standing  in  these  for  some  length  of 
time,  the  oil  becomes  of  a  bright  lemon-yellow  color,  and  is  ready 
for  commerce. 
In  some  oil  mills  the  treatment  with  alkali  to  remove  color  is  not 
carried  as  far  as  is  described  above,  but,  to  complete  the  refining, 
the  oil  is  subsequently  treated  with  bleaching  powder  and  dilute 
sulphuric  acid.  This  plan,  however,  is  now  rarely  employed ;  for, 
since  the  oil  has  to  some  extent  become  an  article  of  food,  the 
unpleasant  odor  and  taste  imparted  by  the  bleaching  powder  would 
condemn  the  brands  purified  by  this  means. 
The  loss  in  refining  the  oil  is  estimated  to  be  from  5  to  8  per 
cent. 
When  the  oil  is  subjected  to  cold  and  pressure  the  stearin  sepa- 
rates, and  much  of  that  used  in  the  manufacture  of  candles,  etc., 
is  now  obtained  in  this  way.  Below  io°  C.  the  oil  solidifies.  It  has 
a  specific  gravity  of  -920  to  -930  at  150  C. 
A  sample  of  cake  meal  was  found  by  the  author  to  contain  8-5 
per  cent,  of  ash.    Nine  per  cent,  of  this  ash  was  silica. 
Two  samples  of  cake  meal  from  different  companies  were  exhausted 
with  petroleum  ether,  in  order  to  ascertain  the  amount  of  oil  con- 
tained. When  the  solvent  was  evaporated,  5-31  and  6  50  per  cent, 
of  oil  were  obtained.  This  points  to  the  fact  that  a  large  part  of 
the  oil  is  not  removed  by  the  pressure  applied. 
Cotton  seed  meal  contains  about  9  per  cent,  of  ammonia  and  8 
per  cent,  of  other  nitrogenous  matter.  The  presence  of  the  latter 
makes  it  a  valuable  food  for  cattle,  the  chief  use  to  which  it  is  put  in 
the  West ;  while  for  the  same  purpose  large  quantities  of  the  meal 
are  annually  exported  to  Germany.  It  is  further  reported  that  some 
of  the  very  poor  people  of  that  country  make  the  meal  into  a 
bread  which  they  say  is  palatable  and  wholesome. 
The  superiority  of  the  cake  meal  over  the  entire  crushed  seed  as 
a  stock  food  lies  in  the  fact  that  the  greater  part  of  the  oil,  which 
has  a  cathartic  action,  has  been  removed. 
The  hulls  also  are  used  as  a  stock  food,  but  are  much  inferior  to 
the  meal. 
On  account  of  its  nitrogenous  constituents,  and  particularly  the 
ammonia,  the  meal  forms  an  excellent  fertilizer. 
