520 
ON  FLUID  EXTRACTS. 
quantity  of  a  butyraceous  mass  floats.  This  possesses  a  penetrating 
odor  of  burnt  fat.  After  the  water  is  removed  from  the  oleaginous 
product,  the  latter  is  distilled  in  an  iron  or  copper  pot,  by  which 
one-third  of  a  very  volatile  and  permanently  fluid  is  obtained  ;  the 
second  third  is  thickly  fluid,  and  the  last  third  solidifies  in  the  cold. 
These  three  different  products  are  treated  in  the  way  recommended 
by  the  author  for  photogene,with  this  difference,  that  instead  of  sul- 
phuric acid  of  spec.  grav.  1-834,  acid  of  spec.  grav.  1-704  is  em- 
ployed. 
By  distillation  with  steam  a  limpid,  light  oil  of  spec.  grav.  0*800, 
possessing  but  little  odor,  is  obtained  ;  to  this  the  author  has  given 
the  name  of  oleone,  with  the  view  of  indicating  at  once  its  origin, 
and  the  similarity  of  its  composition  to  that  of  acetone.  It  is  an 
excellent  lamp  fuel,  and  is  not  subject  to  become  resinified.  It 
may  be  burnt  in  the  same  lamps  as  photogene,  camphine,  and  pino- 
line. 
The  second  product,  which  is  thickly  fluid,  is  free  from  oxygen 
and  not  subject  to  oxidation  in  the  air ;  it  may  be  employed  with 
advantage  for  greasing  the  fine  parts  of  machinery,  and  may  also  be 
burnt.  From  the  third  product  of  the  fractional  distillation  the 
author  prepares  a  solid  hydrocarbon  resembling  paraffme ;  it  forms 
an  excellent  material  for  candles. —  Chem.  Gazette,  Sept.  15,  1858, 
from  Polyt.  Journal,  cxlvii.  p.  304. 
ON  FLUID  EXTRACTS. 
By  Henry  Thayer,  M.  D: 
The  want  of  officinal  formulae  to  govern  the  manipulations 
required  in  the  manufacture  of  Fluid  Extracts,  leads  to  a  diver- 
sity of  quality  and  strength,  as  prepared  by  different  manufac- 
turers. As  the  favor  shown  by  physicians  to  this  class  of 
preparations  increases,  this  want  begins  to  be  felt,  and  the 
attention  of  Pharmaceutists  is  directed  to  the  subject. 
I  propose  in  this  paper,  briefly,  perhaps  imperfectly,  to  state 
the  theory  and  principles  which  I  consider  involved  in  this  branch 
of  Pharmacy. 
I  should  define  a  Fluid  Extract  to  be  a  permanent  concen- 
trated solution  of  the  active  principles  of  a  vegetable  remedy,  of 
known  standard  strength.  It  should  also  be  a  plain  extract  of 
the  plant,  as  much  so  as  a  solid  extract,  that  physicians  may 
