Am.  Jour.  Pharm. 
Aug,  1880. 
Commercial  ^uinia  Sulphate. 
slight,  for  it  must  be  rememhered  that  there  are  but  few  kinds  of  cin- 
chona bark  which  contain  so  much  quinidia  that  its  sulphate  is  likely  to 
remain  mixed  with  recrystallized  quinia  sulphate. 
Quite  recently,  another  paper  on  the  subject  has  been  published  by 
Dr.  Kerner,  in  which  he  specially  refers  to  the  misconceptions  and 
errors  which  he  thinks  have  arisen  from  Dr.  Hesse's  recommendations 
of  a  method  for  judging  as  to  the  quality  of  commercial  quinia  sul- 
phate, and  in  justification  of  this  view  he  instances  the  statement  in  a 
paper  by  Dr.  Schacht,  of  Berlin,  that  a  certain  sample  of  quinia  sul- 
phate, tested  as  Dr.  Hesse  directs,  gave  a  result  showing  that  it  con- 
tained "at  least  3  per  cent,  of  cinchonidia  sulphate."  He  there  men- 
tions having  long  ago  made  use  of  the  method  recommended  by  Dr. 
Hesse,  and  based  essentially  upon  the  fact  that  cinchonia,  quinidia 
and  cinchonidia  dissolve  less  readily  in  ether  and  separate  from  the 
ethereal  solution  more  quickly  when  they  are  associated  with  very  little 
or  no  quinia;  but  he  adds  that  his  experience  at  that  time  led  him  to 
regard  this  mode  of  testing  as  not  being  practical  and  trustworthy 
enough  for  its  adoption  as  an  official  quinia  test.  He  gives  several 
reasons  which  lead  him  to  infer  that  quantitative  estimations  according 
to  the  time  the  appearance  of  crystals  in  the  ether  solution  takes  place 
are  altogether  precarious  and  untrustworthy,  and  then  goes  on  to  state 
that  the  ammonia  test  carefully  applied  is  so  much  more  safe  and  deli- 
cate that  it  will  admit  of  approximate  determination  of  the  impurities 
in  commercial  quinia  sulphate,  besides  giving  positive  evidence  of 
purity  in  the  case  of  samples  that  are  free  from  associated  alkaloids. 
We  propose  publishing  in  an  early  number  of  this  journal  a  resume 
of  the  directions  given  by  Dr.  Kerner  for  applying  the  ammonia  test 
in  order  to  ascertain  the  character  of  commercial  quinia  sulphate,  and 
also  for  the  purpose  of  determining  more  precisely  the  actual  quantities 
of  impurity  present,  and  will  now  only  mention  one  other  point  which 
he  deals  with,  viz.,  the  amount  of  water  in  the  quinia  sulphate  of 
trade.  It  is  well  known  that  this  salt  normally  contains  a  considerable 
amount  of  water  of  crystallization,  and  that  this  water  is  readily  lost 
by  efflorescence.  Besides  this,  the  voluminous  character  of  the  salt 
enables  it  to  hold  mechanically  a  variable  excess  of  water  to  such  an 
extent,  as  Dr.  Kerner  states,  that  apparently  dry  samples  may  be  met 
with  containing  as  much  as  18  per  cent,  of  water.  It  is  also  stated 
that  such  a  result  is  not  unfrequently  brought  about  by  devices  of  the 
manufacturer  and  by  intentional  moistening  of  the  salt  after  it  has 
