A  m.  Jour.  Pharm.  \ 
November,  1899.  J 
Magnesium  Citrate. 
545 
dala  amara,  stramonii  semen,  etc.,  to  exhaust  small  quantities  of  the 
drug  with  suitable  solvents.  Then  in  some  cases  the  active  prin- 
ciples are  removed  from  these  solutions  by  shaking  out  with 
water.  Upon  these  aqueous  solutions  tests  are  then  made  with 
various  reagents,  the  precipitates  of  which  may  be  further  exam- 
ined microscopically.  H.  Behrens,  in  his  "  Anleitung  zur  Mikro- 
chemischen  Analyse,"  has  shown  that  rather  delicate  separa- 
tions may  be  effected  by  the  different  alkaloids  in  drugs.  These 
separations,  however,  must  be  effected  upon  solutions  of  the  alka- 
loids of  the  drugs,  rather  than  upon  the  drugs  themselves.  This 
is  a  most  interesting  field  for  future  work,  and  is  one  teeming  with 
great  possibilities.  One  of  the  recent  papers  on  this  subject  is  that 
by  Zenetti  (Pharm.  Zeit.,  XLII,  p.  752),  in  which  he  has  endeavored 
to  differentiate  the  alkaloids  by  reason  of  the  differences  in  crystal- 
line structure  of  the  precipitates  obtained,  these  being  examined  by 
means  of  a  microscope.  His  results  are  summed  up  as  follows  : 
Strychnine  yields  feathery  crystals  twisted  into  a  sickle  shape,  some- 
times into  corkscrew-like  combinations.  Brucine,  after  two  or  more 
days,  shows  numerously  branched  formations,  with  small,  shingled 
rods  inserted  at  right  angles  on  each  branch.  Atropine  yields,  after 
a  day,  numerously  branched  structures,  the  tips  of  the  branches 
consisting  of  right-angled,  thin,  smooth  plates,  with  smaller  similar 
plates  adherent.  Cocaine  gives  rise  in  a  day  to  the  formation  of 
glittering,  golden  tufts,  consisting  of  acutely  pointed  needles.  Nico- 
tine yields  a  precipitate  which  almost  invariably  takes  the  form  of 
small,  sparsely  branched  rosettes,  composed  of  rigid,  unbranched 
arms,  which  frequently  terminate  in  a  point  or  long  bristle. 
(To  be  continued.) 
MAGNESIUM  CITRATE,  EFFERVESCING,  ADULTERATED 
WITH  MAGNESIUM  SULPHATE. 
By  IvYman  F.  Kebler. 
Recently  the  writer  was  given  a  sample  of  magnesium  citrate, 
effervescing,  with  the  information  that  the  article  was  offered  so 
cheaply  that  its  purity  must  certainly  be  called  into  question. 
Physically,  the  article  was  good.  A  cursory  examination  indicated 
a  large  excess  of  sulphate,  which,  on  estimation,  amounted  to 
24-67  per  cent.,  calculated  as  magnesium  sulphate. 
