594  Valuation  of  Drugs  and  Foods.  { 
to  bacteriology  and  pathology.  Both  of  these  branches  may  be 
looked  upon  as  departments  of  biology.  The  antiseptic  or  germi- 
cidal effect  of  different  substances  upon  harmful  organisms  is  one 
of  the  most  important  subjects,  from  a  practical  standpoint,  that 
may  be  considered.  On  the  one  hand,  the  study  of  the  toxalbu- 
mins  or  proteid  poisons  of  various  micro-organisms,  as  well  as  of 
many  higher  animals,  as  snakes,  spiders,  etc.,  has  opened  up  a  par- 
ticularly inviting  field  during  the  past  ten  years.  The  work  of 
True  and  others,  already  referred  to,  has  done  much  to  clear  up 
the  mystery  surrounding  this  subject,  and  we  hope  that  the  prac- 
tical application  of  the  work  of  these  authors  may  be  fully  appreci- 
ated. By  experiments  of  the  nature  proposed,  the  question  can  be 
satisfactorily  answered,  what  is  the  least  amount  of  antiseptic  or  anti- 
dote that  is  necessary  to  produce  the  neutralization  of  the  poison  or 
death  of  the  organism  producing  the  poison? 
(2)  The  valuation  of  insect  powder  has  been  attempted  in  a  num- 
ber of  ways,  depending  upon  amount  of  ash,  color  and  per  cent,  of 
extract,  microscopical  characters,  direct  effect  upon  flies  and  other 
insects.  Probably  the  most  satisfactory  method  is  to  take  about 
0-250  gramme  of  the  powder,  place  it  in  a  small  homeopathic  vial 
and  subject  an  insect  (say  a  fly)  to  its  influence.  The  latter  should 
be  paralyzed  in  one  minute  and  killed  in  about  two  or  three 
minutes.  Other  insects,  as  cockroaches,  beetles,  etc.,  manifest 
more  resistance  to  its  effects,  and  may  not  be  killed,  accord- 
ing to  J.  R.  Hill,  for  fifty  or  sixty  hours.  It  is  interesting  to 
note  from  the  experiments  of  J.  M.  Francis  that  much  valuable 
substance  may  be  lost  unless  experiments  of  this  kind  are  car- 
ried out.  He  found,  upon  experimenting  with  three  different 
powders:  (1)  made  from  the  flowers  only;  (2)  made  from  the 
stems  only;  (3)  made  from  an  equal  mixture  of  flowers  and  stems, 
that  when  these  powders  were  sprinkled  or  blown,  by  means  of  the 
"powder  gun,"  on  flies  and  other  insects  in  traps,  or  on  dogs  in- 
fested with  fleas,  there  was  seemingly  no  difference  in  the  rapidity 
of  action  or  toxicity  of  that  made  from  flowers  and  that  made  from 
both  flowers  and  stems.  The  powder  made  from  stems  alone,  how- 
ever, appeared  a  little  weaker,  but  even  this  showed  a  surprising 
activity. 
These  results  point  again  to  the  fact  that  in  practice  what  is 
desired  is  an  insecticidal  powder  that  will  simply  do  the  work,  and 
