250 
Myrtus  Cheken. 
(  Am.  Jour.  PharmL 
t      May,  1883. 
4.  Estimation  of  Benzin  Extract — 622*08  gms.  of  powdered  leaves,, 
dampened  with  petroleum  benzin  and  packed  in  a  glass  percolator, 
were  macerated  for  two  days,  and  then  slowly  exhausted  by  displace- 
ment. The  percolate,  which  measured  189  liters,  was  set  aside  in  a 
tared  dish  to  evaporate  spontaneously,  and  yielded  32*98  gms.,  or  5*3 
per  cent,  of  extract.  This  extract  was  treated  with  water,  which  gave 
a  solution  depositing  upon  concentration  a  bright  yellow  coloring 
matter ;  a  solution  of  this  was  neutral,  and  when  tested  for  the  presence 
of  glucosides  by  Trommers'  test,  gave  negative  results.  The  residue 
was  then  subjected  to  the  action  of  alcohol,  which  dissolved  out  vola- 
tile oil,  chlorophyll,  and  left  on  evoporation  a  small  amount  of  an 
inodorous,  light  yellow,  bland  fixed  oil.  The  residue  of  matter  left 
consisted  of  fixed  oil,  wax,  and  tasteless  extractive  matter. 
5.  Estimation  of  Alcoholic  Extract. — The  residue  of  leaves  from  the 
preceding  examination  was  treated  with  alcohol  (90  per  cent.),  1*89' 
liters  of  percolate  was  obtained.  One-half  of  this  percolate  was  reduced 
to  an  extract  weighing  31*73  gms.,  or  10*2  per  cent,  of  the  whole,  and 
was  of  a  dark  green  color,  odorless,  tough  and  astringent.  The  other 
half  of  the  percolate  reduced  to  a  syrupy  consistence,  was  strongly 
agitated  witli  acidulated  water,  precipitation  ensued.  The  solution 
was  filtered  and  the  precipitated  matter  dissolved  in  ether;  this,  when 
spontaneously  evaporated,  left  an  odorless,  resinoid  body,  tough,, 
leathery,  and  of  a  greenish-black  color ;  its  weight  was  3*33  gms.,  or 
5*2  per  cent,  of  the  extract.  The  alcoholic  solution  of  the  resin  was 
neutral  in  its  reactions.  Its  solution  in  potassium  hydrate  was  yellowish- 
brown,  and  readily  precipitated  by  mineral  acids. 
The  filtrate  of  the  above  was  concentrated,  and  found  to  contain 
tannin,  in  small  amount,  accompanied  by  dark  brown  extractive 
matter,  slightly  bitter,  freely  soluble  in  dilute  alcohol,  but  insoluble 
in  water. 
6.  Estimation  of  Hydro-alcoholic  Extract. — The  residue  of  leaves  left 
from  the  previous  exhaustion  by  alcohol  was  next  displaced  with  diluted 
alcohol.  The  percolate  measured  2*84  liters.  One-half  of  the  percolate 
reduced  to  an  extract  gave  19*44  gms.,  or  6*25  per  cent,  of  the  whole. 
To  the  remaining  portion  of  the  percolate  a  solution  of  basic  acetate 
of  lead  was  added,  the  precipitate  formed  was  separated  by  filtration^ 
and  the  filtrate  (a)  reserved.  After  thoroughly  washing  the  precipitate 
and  suspending  in  water,  it  was  decomposed  by  gaseous  hydrogen  sul- 
phide and  the  filtrate  tested  for  the  presence  of  tannin,  giving  a  blue- 
