ArnFeb.ni894arm"} Analysis  of  Pycnanthemum  Lanceolatum.  69 
being  equivalent  to  the  percentage  of  cellulose,  etc.,  stated  in  the 
table. 
A  portion  of  the  original  powdered  herb  was  tested  for  tannin  by 
extraction  with  cold  water  ;  a  brown  solution  being  obtained,  which 
gave  brown  precipitates  with  ferric  chloride  solution,  and  with  a 
mixture  of  ferric  chloride  and  ferrous  sulphate  solutions  ;  and  a 
light  brown  precipitate  with  solution  of  gelatine  containing  alum, 
but  a  similar  precipitate  was  obtained  with  solution  of  alum  alone. 
The  residue  from  the  above  extraction  with  cold  water  was  boiled 
with  water,  and  the  solution  tested  with  iodine  for  starch,  which 
was  not  detected. 
Special  tests  were  also  made  with  some  of  the  original  powdered 
herb,  for  alkaloids  and  glucosides,  with  negative  results. 
In  drawing  conclusions  from  the  analysis,  the  absence  of  tannin 
and  starch,  and  the  small  quantities  of  inulin  and  sugar  may  be 
noted  ;  also,  the  failure  to  find  either  alkaloids  or  glucosides,  as 
above  stated. 
NOTES  ON  THE  ETHEREAL  OIL. 
The  oil  was  obtained  by  distilling  the  material,  broken  into  short 
lengths,  with  water,  in  which  it  was  soaked  overnight  before  dis- 
tilling. The  aqueous  portion  of  the  distillates  was  returned  to  the 
still,  with  the  exception  of  that  obtained  in  the  last  distillation, 
which  was  shaken  out  with  benzol ;  the  separated  benzol  solution 
left,  on  evaporation  of  the  solvent,  a  small  quantity  of  oil,  which 
was  added  to  the  main  quantity. 
The  total  amount  obtained  weighed  about  5  3-47  grammes,  which 
was  equivalent  to  about  1-47  per  cent,  of  the  air-dry  material. 
The  following  of  its  properties  were  ascertained  : 
Color  pure  yellow,  of  medium  depth. 
Odor  considerably  resembling  that  of  pennyroyal. 
Specific  gravity,  at  150  C,  -936 1 . 
The  boiling  points  were  determined  by  heating  on  a  sand  bath  in 
a  test-tube,  the  thermometer  bulb  being  completely  immersed  in  the 
oil.    The  temperature  was  allowed  to  rise  slowly. 
At  1500,  boiling  commenced,  very  gently. 
At  205 °,  the  ebullition  had  become  rather  more  brisk,  but  still 
very  gentle. 
Between  2100  and  2 1 5 0  it  became  much  stronger. 
The  temperature  finally  rose  to  2160,  but  did  not  then  remain 
