472  Leaves  of  Juglans  Nigra.  {Am"octuri£6.arm" 
under  sulphuric  acid  and  left  little  residue  on  platinum.  It  did 
not  blacken  ferric  chloride;  it  reduced  Fehling's  solution;  it  gave 
no  reactions  with  Mayer's  solution,  triiodide  of  potassium,  cadmium 
iodide,  gold  or  platinum  chloride.  It  must  then  be  glucosoidal  in 
nature. 
That  part  of  alcoholic  residue  insoluble  in  water  alone,  in  water 
acidified  by  sulphuric  acid  and  in  ammonia,  was  found  to  contain  resin. 
Chlorophyll,  tannin,  a  glucoside,  coloring  matter  and  resin,  were  found 
in  the  alcoholic  extract. 
The  water,  acid  and  alkaline  extractions,  were  made  only  upon  the 
residual  powder  from  the  ten  grams.  Treatment  was  continued  for 
about  three  days,  the  solvents  being  replaced  daily  and  the  portions 
filtered  oft0  preserved  by  adding  a  little  alcohol. 
Residue  after  treatment  with  alcohol,  was  dried  at  a  little  above 
ordinary  temperature  until  alcohol  odor  had  almost  disappeared,  and 
then  treated  with  cold  water.  The  water  extract  amounted  to  14.50 
per  cent.,  the  ash  was  2.00  per  cent.,  making  organic  extract  12.50 
per  cent.  The  green  and  pink  particles  in  the  ash  were  very  noticeable. 
The  water  extract  had  the  color  of  port  wine.  Residue  was  brown  in 
color  and  odorless.  Nitrogen  was  found  in  it.  Tests  showed  all  the 
tannin  had  been  removed.  An  aliquot  part  of  extract  was  mixed  with 
two  volumes  of  alcohol  and  allowed  to  stand  twenty-four  hours.  The 
precipitate  obtained  was  washed  with  alcohol  and  then  dried.  It  gave 
3.20  per  cent,  of  which  .80  per  cent,  was  ash.  This  precipitate  was 
dark  brown  in  color,  almost  wholly  soluble  in  water  to  mucilaginous 
liquid,  and  reduced  Fehling's  solution.  Part  of  the  filtrate  from  the 
gum  precipitate  was  evaporated  to  a  syrupy  consistency  and  four  volumes 
of  alcohol  added.  A  slight  precipitate  proved  that  a  trace  of  dextrin 
and  other  carbohydrates  were  present.  The  filtrate  from  this  precipi- 
tate reduced  Fehling's  solution.  Fehling's  solution  applied  to  a 
measured  portion  of  the  original  water  extract  gave  1.14  per  cent, 
glucose.  As  was  anticipated  by  the  results  above,  the  same  quantity 
of  water  extract  after  being  boiled  with  sulphuric  acid  did  not  give  an 
appreciable  greater  amount  of  glucose. 
An  aliquot  part  of  the  filtrate  from  the  gum  precipitate  was  concen- 
trated and  afterwards  precipitated  with  neutral  lead  acetate.    The  pre- 
cipitate amounted  to  9.80  per  cent.,  of  which  6.00  per  cent,  was  lead, 
oxide.    The  organic  acids  and  allied  substances  amounted  to  3.80  per 
cent.    An  unsuccessful  attempt  was  made  to  identify  the  acids.  The 
