408  Gleanings  from  the  German  Journals,  {Am'A^;S^m' 
tralized  as  the  first  portion  may  be  decolorized  through  the  liberation 
of  small  quantities  of  chlorine  before  the  alkali  has  been  neutralized. 
(3)  25  cc.  are  diluted  with  water  and  a  little  cobalt  or  nickel  ses- 
quioxide  suspended  in  water  added ;  after  gradual  heating  (to  pre- 
vent a  violet  reaction)  the  mixture  is  boiled,  diluted  with  water  to 
250  cc,  filtered,  and  in  100  cc.  (10  cc.  original  solution)  the  sodium 
hydrate  and  carbonate  are  determined  as  under  the  first  method. 
All  three  methods  give  satisfactory  results  ;  No  2  after  some 
practice  is  to  be  preferred  owing  to  rapidity. —  Chcmikcr  Ztg.,  1892, 
885. 
Syrup  of  ferrous  iodide,  according  to  A.  Bernick,  is  a  delicate 
reagent  for  ammonia,  the  color  being  changed  to  yellow  or  brown  ; 
this  color  is  destroyed  by  boiling  or  by  the  addition  of  citric  acid. 
It  is  thought  that  this  is  the  explanation  of  the  change  in  color  that 
the  syrup  sometimes  shows;  at  the  same  time  the  remedy  suggests 
itself,  either  to  boil  such  a  syrup,  or  to  add  a  little  citric  acid  
Pharm.  Ztg.,  1892,  373. 
Constituents  of  insect  powder. — In  continuing  their  investigations, 
Schlagdenhauffen  and  Reeb  obtained,  by  distilling  Dalmatian  insect 
powder  with  steam,  a  pale  yellow  oil  of  a  chamomile-like  odor,  in 
which  is  suspended  a  small  quantity  of  a  crystalline  substance.  The 
aqueous  distillate  contains  formic,  acetic  and  propionic  acids  and 
another  organic  acid,  which  was  found  to  be  poisonous,  called 
chvysanthemic  acid]  the  sodium  salt  of  this  acid  is  insoluble  in 
alcohol.  The  residue  from  the  distillation  was  found  to  still  have 
toxic  properties  ;  by  extracting  this  residue  with  petroleum  ether, 
evaporating,  dissolving  in  alcohol,  neutralizing  with  potassa,  evap- 
orating to  dryness,  taking  up  with  water,  filtering,  acidifying  filtrate 
with  tartaric  acid,  extracting  with  ether  and  evaporating  the  ethe- 
real solution  another  poisonous  acid,  pyrethrotoxic  acid,  was  obtained 
as  a  yellow,  uncrystallizable,  buttery  mass,  which  was  found  very 
easily  soluble  in  alcohol,  chloroform,  benzin,  benzol,  acetic  ether 
and  acetone.  Caucasian  insect  powder  yields  almost  identical 
results. — Chem.  Centr.-Blatt ;  Pharm.  Ztg.,  1892,  374. 
Iodoform  deodorizer. — Apparatus  in  which  iodoform  preparations 
have  been  made  can  be  freed  from  every  trace  of  the  odor  by  the 
addition  of  a  few  drops  of  laurel  oil  before  cleaning  the  apparatus 
with  saw-dust.  The  odor  of  the  laurel  oil  disappears  in  a  very 
short  time.— F.  K.,  Pharm.  Ztg.,  1892,  396. 
