AmNo°vUr'i92iarm' }     Scientific  and  Technical  Abstracts.  803 
of  water,  and  the  flask  disconnected.  A  further  1  gin.  of  sodium 
carbonate  is  added,  and  the  mixture  boiled  gently  for  20  minutes-; 
care  must  be  taken  during  this  period,  as  the  evolution  of  carbon 
dioxide  causes  much  frothing.  The  precipitate  is  then  collected  on 
a  weighed  filter,  washed  with  not  less  than  200  cc.  of  hot  water, 
dried  at  ioo°  C.  and  weighed.  The  weight  found  is  multiplied  by 
0.3 1 13  to  obtain  the  amount  of  salol  present.  Acetanilide,  phenace- 
tin,  and  caffeine  do  not  interfere  with  the  estimation,  but  when 
phenacetin  is  known  to  be  present,  the  quantity  of  iodine  should  be 
increased  by  5  cc.  for  each  0.1  gm.  of  phenacetin.  With  a  mixture' 
of  salol  and  acetanilide,  the  filtrate  from  the  precipitate  is  practi- 
cally colorless ;  but  when  phenacetin  is  present  the  filtrate  is  colored 
light  yellow,  so  that  it  is  not  easy  to  recognize  whether  or  not  an 
excess  of  iodine  is  present. — Emery  (/.  Ind.  Eng.  Chem.,  192 1,  pp. 
538-539,  through  Analyst,  1921,  p.  376). 
Estimation  of  Lecithin. — In  Hager's  method  of  estimation 
the  lecithin  is  decomposed  by  boiling  with  nitric  and  sulphuric  acids, 
and  the  phosphoric  acid  precipitated  with  ammonium  molybdate. 
The  precipitate  is  washed,  suspended  in  water,  and  dissolved  in 
semi-normal  alkali  hydroxide  solution,  an  excess  of  5  to  6  cc.  being 
added,  and  the  solution  boiled  until  all  ammonia  is  expelled,  and 
then  titrated  with  semi-normal  hydrochloric  acid.  Each  cubic  centi- 
metre of  decinormal  alkali  corresponds  (according  to  Hager)  with 
1.268  mgm.  of  P2O5.  The  author  finds  this  method  tedious  and 
quite  unreliable.  The  phosphoric  acid  may  be  estimated  directly 
in  the  residue  obtained  after  removal  of  organic  matter  by  a  mix- 
ture of  nitric  sulphuric  acids.  The  acid  is  first  neutralized  with 
alkali,  and  ammonium  chloride  and  ammonia  are  added  until  a 
precipitate  forms,  which  is  then  dissolved  in  dilute  hydrochloric 
acid.  Magnesia  mixture  is  added,  and  the  solution  is  treated  with 
ammonia  at  boiling  temperature.  It  is  not  possible,  however/ to  de- 
termine the  amount  of  lecithin  in  a  sample  from  its  P2O5  content,  as 
the  formula  C42HS4NPO9  is  doubtful. —  (J.  L.  B.  Van  der  Marck, 
Pharm.  Weekblad.,  192 1,  989-992,  through  Chem.  and  Drugg.) 
Fat-Soluble  Vitamin  and  Yellow  Pigmentation  in  Ani- 
mal Fats. — There  is  a  very  high  concentration  of  the  fat-soluble 
vitamin  in  cod  liver  oil,  but  only  small  amounts  of  yellow  pigments. 
