Am.  lour.  Pharni. ) 
June,  1881.  / 
Chemical  Notes. 
295 
stand  for  a  week.  The  abundant  precipitate  which  forms  is  then 
washed,  first  with  cold  and  then  with  boiling  absolute  alcohol.  The 
product  so  obtained  (10  grams)  is  a  white  amorphous  hygroscopic 
but  not  deliquescent  powder,  which  contains  alcohol  and  has  the 
composition  CigHggOi^.Cg^gO.  It  loses  the  alcohol  at  110°  and  remains 
as  a  very  hygroscopic  and  deliquescent  powder.  On  boiling  with 
water  the  alcohol  compound  is  decomposed  and  there  is  obtained  a 
substance  of  the  composition  (C\-HiqH5)3  =  C^^H.jfi^^,IioO,  a  yellow 
amorphous  mass,  very  easily  soluble  in  water,  of  sweetish  taste,  which 
is  not  colored  by  iodine,  is  precipitated  by  alcohol  from  aqueous  solu- 
tion, only  slightly  reduces  Fehling's  solution,  possesses  a  rotatory 
power  of  131°  to  134°,  is  not  brought  to  fermentation  by  yeast  or  by 
diastase,  but  by  several  hours'  boiling  with  4  per  cent,  sulphuric  acid 
is  changed  into  sugar.  Musculus  considers  it  like  the  ^'-dextrine 
described  by  him  previously. — Compt.  Rend.,  92,  p.  528. 
Gallic  Acid  Reaction. — According  to  Dudley,  ammonium  picrate 
added  to  gallic  acid  solutions,  produces  at  first  a  reddish  color  which 
after  a  few  seconds  changes  into  fine  green.  Pyrogallic  acid  and 
tannin  give  also  a  reddish  color  but  it  is  not  further  changed.  —  Chem, 
Industrie,  April,  1881,  p.  129. 
Technical  Chemistry. — Fatty  Acids  and  Allied  Products. — Prof. 
J.  W.  Mallet,  in  his  review  of  recent  advances  in  applied  chemistry, 
gives  the  following :  In  the  important  manufacture  of  the  fatty  acids, 
the  three  processes  now  chiefly  in  use  are,  1st.  Decomposition  by 
means  of  sulphuric  acid  and  distillation  with  the  aid  of  superheated 
steam ;  2d.  Saponification  by  lime  in  closed  vessels  under  pressure, 
and  decomposition  of  the  lime-soap  by  sulphuric  acid ;  3d.  Saponifi- 
cation by  lime  as  before,  followed  by  treatment  with  a  small  excess  of 
sulphuric  acid  and  distillation  in  a  current  of  superheated  steam. 
Lime  is  chiefly  used  by  the  smaller  manufacturers,  sulphuric  acid, 
followed  by  distillation,  in  the  larger  establishments.  By  far  the  most 
interesting  novelty  in  this  field  of  industry  is  the  appearance  in  the 
market,  introduced  by  two  French  manufacturers,  of  palmitic  acid 
artificially  made  from  oleic  acid  by  heating  with  strong  potash  lye  at 
300°  to  325° C,  thus  producing  potassium  palmitate  and  acetate,  to  be 
separated  by  washing  with  a  limited  quantity  of  water,  the  former 
salt  to  be  then  decomposed  by  sulphuric  acid.  The  quantity  of  caus- 
tic potash  required  is  said  to  be  large — twice  the  weight  of  the  oleic 
acid  treated — but  it  is  recovered,  the  acetate  of  potassium  being 
