364 
Insect  Powders  of  Commerce. 
Am.  Jour.  Pharm. 
July,  1897. 
microscopically,  but  it  yields  10  per  cent,  of  ash,  whereas  true  insect 
powder  yields  but  6  5  per  cent.  On  this  point  the  reader  is  referred 
to  an  extract  from  a  paper  by  J.  Schrenk  (American  Journal  of 
Pharmacy,  1889)  in  the  "Year  Book,"  1890. 
It  is  hoped  that  it  will  not  be  difficult  to  accept  my  contention 
that  by  the  term  insect  powder  it  is  intended  by  both  buyers  and 
sellers  that  powder  of  the  flowers  of  the  C.  cinerarisefolium  is  under- 
stood, at  least  so  far  as  transactions  in  the  open  market  are  con- 
cerned. O  wners  of  proprietary  insect  powders  have  a  right  to  com- 
pound them  as  they  please,  and  this  right  has  been  freely  exercised 
by  the  use  of  powdered  quassia,  colocynth,  etc.,  as  well  as  by  the 
addition  of  various  coloring  agents.  Although  powdered  quassia 
mixed  with  powdered  insect  flowers  must  be  considered  to  fall 
under  our  definition  of  adulteration,  it  is  quite  possible  that  a  small 
proportion  is  useful  in  insect  powder,  increasing  or  broadening  the 
base  of  its  usefulness.  The  same  remarks  apply  to  other  admix- 
tures, such  as  powdered  bitter  apple,  and  the  only  criticism  to  be 
made  on  this  point  is  that  if  powdered  quassia  or  other  powders 
having  insecticidal  properties  be  added  to  insect  powder,  let  it  be 
done  with  the  knowledge  of  buyers  and  at  the  proper  price. 
The  adulterants  just  referred  to  are  for  the  most  part  things  of 
the  past,  with  the  exception  of  added  coloring  matters,  which  are 
still  very  commonly  used  to  meet  the  too  general  want  of  knowl- 
edge of  the  proper  appearance  of  true  insect  powder.  At  the  pres- 
ent time  the  insect  powders  of  commerce  may  be  divided  into  the 
following  classes : 
(1)  Ground  from  closed  (a)  wild,  or  (b)  cultivated  flowers  of  C. 
cinerariaefolium. 
(2)  Ground  from  half-open  or  mixed  half-open  and  open  flowers. 
(3)  Ground  from  damaged  flowers. 
(4)  Foreign-ground,  divided  into  grades  of  badness  under  the 
meaningless  terms:  "closed  flowers,"  "half-open  flowers,"  etc.,  etc. 
Of  these  sorts  there  appears  to  be  as  many  as  there  are  of  hens' 
eggs,  which  embrace  all  the  kinds  between  "new-laid"  at  the  top 
of  the  list,  and  "political"  at  the  bottom.  The  English-ground 
insect  powders  do  not  always  justify  the  description  given,  but  in 
my  experience,  the  foreign-ground  specimens  never  do,  and  it  is 
with  much  satisfaction  that  it  is  noted  that  a  ready  method  of  dis- 
tinguishing "foreign-ground"  is  to  hand. 
