472 
Assay  of  Drugs. 
(  Am.  Jour.  Pharm. 
t     October,  1900. 
Observe  that  oxidation  does  not  begin  before  the  preparation  has 
been  finished. 
Remember  that  a  darkening  color  does  not  always  indicate 
presence  of  iodine ;  it  may  be  due  to  the  fact  that  caramelization 
has  begun. 
It  is  bad  pharmacy  to  reclaim  syrup  ferrous  iodide  too  often. 
Always  boil  the  water  before  using,  to  dispel  ammonia,  carbon 
dioxide  and  other  volatile  impurities. 
It  is  a  good  point  when  following  the  official  directions  to  "  heat 
the  solution  to  boiling,"  after  "  having  lost  the  odor  of  iodine,"  to 
heat  the  solution  in  a  water-bath,  for  by  the  use  of  direct  heat  the 
solution  is  often  slightly  reddened,  due  to  a  scorching  caused  by 
too  high  temperature. 
Filter  always  through  rapid-acting  Swiss  (or  otherwise  pure)  filter 
paper. 
We  deem  it  a  good  plan  to  heat  the  finished  syrup  to  boiling,  to 
dispel  any  free  iodine,  by  converting  it  to  hydriodic  acid  by  the  aid 
of  the  invert  sugar  caused  by  boiling  the  cane  sugar  solution. 
ASSAY  OF  DRUGS  BY  THE  USE  OF  LIVING  PLANTS.1 
By  Henry  Kraemer. 
While  I  have  a  certain  amount  of  hesitation  in  presenting  the 
results  recorded  in  this  paper  at  the  present  time,  it  nevertheless 
seems  to  me  that  more  would  be  gained  by  such  a  procedure  than 
by  withholding  them  for  a  longer  time  in  order  to  accumulate  more 
data,  and  in  support  of  this  position  permit  me  to  quote  the  follow- 
ing from  Montesquieu:  "  When  you  treat  a  subject,  it  is  not  neces- 
sary to  exhaust  it,  it  is  enough  if  you  cause  thought." 
The  subject  of  the  testing  of  drugs  by  means  of  their  effects  upon 
living  plants  is  not  an  entirely  new  one,  as  I  supposed  and  ventured 
to  state  in  my  paper  on  "  The  Valuation  of  Drugs  and  Foods  "  a  year 
ago.  In  fact,  methods  of  this  kind  have  been  employed  to  a  consider- 
able extent  in  Europe  and  appear  to  be  of  fundamental  importance  in 
ascertaining  the  toxic  properties  and  therapeutic  value  of  drugs. 
No  less  an  authority  than  Kobert,  in  his  41  Lehrbuch  der  Intoxi- 
cationen  "  (1893),  says  that,  after  one  has  obtained  the  substance 
relatively  pure  and  made  a  neutral  solution,  "  Der  Gang  der  Unter- 
suchung  ist  nun  der,  dass  man  erst  den  Einfluss  auf  moglichst 
1  Presented  at  the  American  Pharmaceutical  Association  meeting,  May,  1900. 
