472 
Alkaloidal  Assays. 
J  Am.  Jour.  Pharm. 
I     October,  I8t9. 
ASSAY  OF  IPECACUANHA. 
For  extraction  of  the  drug,  use  one  of  the  methods  given  in 
Lyons'  "  Assaying." 1  The  cold  percolation  process  of  extraction  pre- 
viously directed,  as  already  remarked,  does  not  work  well  with  this 
drug.2 
In  iodometric  estimation  the  total  acidulated  alkaloid  solution  is 
made  up  to  a  definite  volume,  an  aliquot  portion  taken,  and  added 
to  a  measured  excess  of  the  iodine  solution,  as  directed  heretofore. 
The  iodine  factor  of  emetine  is  taken  as  fairly  near  the  mean  factor 
of  the  total  alkaloids. 
ASSAY  OF  HYDRASTIS. 
In  the  assay  of  Hydrastis  canadensis ,  for  berberine  and  for  hy- 
drastine,  the  directions  for  the  assays  are  given  in  the  accompany- 
ing article  entitled  "  Further  Work  Upon  the  Estimation  of  Alka- 
loids," etc.  In  the  plan  of  the  assay  the  hydrastine  is  dissolved 
with  absolute  ether,  and  estimated  iodometrically  as  a  hexiodide. 
The  berberine,  undissolved  by  the  absolute  ether,  is  estimated  volu- 
metrically  by  precipitation  as  berberine  hydriodide,  the  excess  of 
the  precipitant,  potassium  iodide,  being  determined  by  silver  nitrate 
with  sulphocyanate.  But  before  the  berberine  is  precipitated  as 
hydriodide,  it  is  separated  in  its  acetone  compound.  And  before 
the  alkaloids  are  acted  upon  by  the  reagents,  they  are  liberated 
from  the  powdered  drug  by  maceration  with  an  ethereo-ammoniacal 
mixture. 
The:  Destruction  of  Mosouitoes  with  Kerosene. — An  interesting  ex- 
periment, confirmatory  of  the  efficacy  of  the  plan  proposed  by  Mr.  Howard, 
of  the  United  States  Department  of  Agriculture,  for  exterminating  those  vexa- 
tious vehicles  of  malaria,  mosquitoes,  was  recently  made  in  England,  as  we 
learn  from  the  British  Medical  Journal  for  July  8th.  Five  drops  of  kerosene, 
added  to  a  bucket  of  water  estimated  to  contain  between  four  and  five  hundred 
larvae,  killed  them  all  within  an  hour,  and  a  teaspoonful  killed,  within  a  few 
hours,  the  many  thousands  contained  in  the  water  of  a  tank  of  nearly  three 
hundred  cubic  feet  capacity. — New  York  Medical  Journal. 
1  Detroit,  1899. 
2  Ether,  chloroform  and  acetone  were  tried  as  menstrua  in  the  cold  percola- 
tion, but  the  results  were  too  low.  The  ammoniated  mixture  fails  to  yield  all 
the  alkaloid.  This  possibly  explains  why  Fliickiger,*  extracting  by  ammoni- 
ated chloroform,  obtained  exceptionally  low  results.  See  also  Guareschi,  "Al- 
kaloide,"  1896,  p.  527. 
*  Pharm.  Zeitung,  1886,  p.  30. 
