582  Supposed  Alkaloid  of  Podophyllum.    { Amb{Z'Zttm° 
at  the  last  meeting  (see  November  number,  p.  543)  does  not  com- 
pletely remove  the  doubt.  The  mother-liquors  from  his  experiments 
were  presented  and  exhibited  at  the  last  meeting,  and  by  Mr.  Biddle 
kindly  placed  at  my  disposal  for  further  investigation.  One  of  the 
samples  consisted  of  the  concentrated  washings  of  the  resin  prepared 
from  the  rhizome  collected  in  March  and  April  (No.  1);  the  other 
was  a  similar  mixture  obtained  from  the  rhizome  collected  in  May, 
July  and  October  (No.  2)  ;  the  latter  had  yielded  the  slightest  reaction 
with  Mayer's  reagent. 
The  two  samples  were  set  aside  for  about  a  week,  after  which  time 
both  had  separated  a  slight  precipitate,  and  the  clear  liquids  yielded  no 
turbidity  at  all  with  Mayer's  test.  The  liquid  No.  1  was  somewhat 
concentrated,  allowed  to  cool,  and  filtered  when  it  was  rendered  turbid 
on  the  addition  of  the  test.  It  was  now  evaporated  to  a  syrupy  con- 
sistence, and,  after  standing  for  about  two  weeks,  filtered  from  the  resin- 
ous deposit,  a,  mixed  with  a  little  hydrochloric  acid,  and  after  24  hours 
again  filtered  from  the  precipitate,  b.  The  filtrate  was  rendered  decid- 
edly turbid  on  the  addition  of  potassio-mercuric  iodide.  A  portion  of 
the  acid  liquid  Was  agitated  with  ether  ;  the  remaining  portion  was  first 
rendered  alkaline  by  the  addition  of  sodium  carbonate,  and  then  like- 
wise treated  with  ether.  In  both  cases,  on  the  complete  evaporation  of 
the  ether,  a  yellowish  amorphous  mass,  of  a  rather  disagreeable  odor, 
was  left,  which  was  agitated  with  dilute  hydrochloric  acid,  the  solutions 
being  arterwards  again  tested  with  Mayer's  reagent,  without  producing, 
the  slightest  turbidity. 
The  resinous  deposit,  was  dissolved  in  a  little  alcohol,  the  solution 
filtered,  the  filtrate  precipitated  by  cold  water  acidulated  with  hydro- 
chloric acid,  and  on  the  following  day  again  filtered.  The  clear  liquid 
gave  no  reaction  with  potassio-mercuric  iodide,  until  after  it  had  been 
concentrated,  cooled  and  filtered.  It  was,  however,  noticed  that  the 
turbidity  again  disappeared,  after  a  short  time,  while  on  other  occasions 
it  remained.  The  cause  for  this  different  behavior  was  only  deter- 
mined after  many  repetitions,  and  was  found  to  be  a  slight  increase  of 
temperature  caused  by  the  radiating  heat  from  a  heated  iron  plate,  or 
by  the  accidental  exposure  of  the  test-tube  to  the  direct  rays  of  the 
sun  ;  in  fact  the  warmth  of  the  hand  was  found  to  be  sufficient  for 
making  the  turbidity  disappear  entirely  or  partly.  The  cold  liquid  was- 
now  completely  precipitated  by  Mayer's  test  ;    the  precipitate,  which, 
