VERIFICATION  OF  CASTOR  OIL  AND  BALSAM  COPAIBA,  ETC.  249 
We  still  procure  large  quantities  of  the  oil  from  the  East 
Indies,  but  that  country  has  now  a  rival,  threatening  to  become 
formidable,  much  nearer  home.  In  the  International  Exhibi- 
tion Italy  had  a  great  show  of  castor  oils.  One  firm  at  Legano 
is  said  to  produce  45  tons  of  oil  every  year,  the  produce  of 
about  120  tons  of  seed.  At  this  establishment,  presided  over 
by  M.  Valeri,  the  machinery  for  cleaning  and  sorting  the  seeds, 
the  hydraulic  presses,  and  the  filtering  apparatus,  are  said  to  be 
well  arranged.  The  oil  cake  is  in  great  demand  as  a  manure 
for  hemp.  The  oil  is  also  used  for  burning,  and  in  some  places 
for  making  soap,  this  oil  saponifying  more  easily  than  olive  oil. 
The  cultivation  of  castor  oil  is  said  to  be  increasing  in 
France  ;  the  yield  is  very  great,  a  single  plant  from  one  seed 
producing  upwards  of  800  or  900  seeds.  The  seeds  sometimes 
yield  more  than  half  their  weight  of  oil.  The  French  and  Ital- 
ian oils  are  weaker  than  those  from  the  tropics.  Italian  oil, 
prepared  in  Italy,  of  which  there  are  some  samples  on  the 
table,  is  a  good  bland  oil.  There  are  also  other  specimens,  pre- 
pared in  this  country  from  decorticated  Italian  seeds. 
The  oil,  as  you  know,  is  very  viscid,  the  color  is  yellowish, 
the  taste,  or  rather  after-taste,  somewhat  acrid,  varying  however 
with  the  freshness  of  the  oil,  and  the  mode  of  preparation.  It 
retains  its  fluid,  viscid  character  probably  as  low  as  0°F.  It 
differs  from  other  fixed  oils  in  being  soluble  in  alcohol,  a  prop- 
erty which  was  long  regarded  as  a  test,  until  Pereira  pointed 
out  the  fact  that  castor  oil  enables  other  fixed  oils  to  dissolve 
in  alcohol  to  the  extent  of  30  per  cent,  and  upwards,  so  that  a 
specimen  may  be  mixed  with  olive,  lard,  nut,  and  other  oils, 
and  yet  be  soluble  in  alcohol.  For  example,  one  volume  of 
olive  oil,  two  volumes  of  castor  oil,  and  two  of  rectified  spirit, 
shaken  together  and  gently  heated,  will  form  a  transparent  ho- 
mogeneous solution.  Benzoic  acid  and  camphor  also  increase 
the  solubility  of  castor  oil  in  spirits  containing  75  per  cent,  of 
alcohol  (sp.  gr.  0-860).  What  is  called  concentrated  castor  oil 
is  common  castor  oil  mixed  with  a  small  proportion  of  croton 
oil,  which  also  enables  other  fixed  oils  to  dissolve  in  alcohol  to 
the  extent  of  from  30  to  50  per  cent. 
It  is  superfluous  to  remark  in  this  place  that  the  distinction 
between  chemistry  and  physics  is  not  recognized  by  nature. 
