EXAMINATION  OF  THE   SULPHATE  OF  QUINIA. 
507 
is  because  I  refrained  from  saying  anything  in  regard  to  them 
that  was  not  based  upon  accurately  detailed  experiment. 
If,  however,  my  deductions  and  conclusions  in  regard  to  them 
are  needed  to  render  the  remarks  more  definite,  I  have  certainly 
no  objections  to  state  them,  qualified  by  the  remark  that  I  did 
not  take  the  time  and  trouble  that  would  be  necessary  to  satisfy 
others  than  myself  upon  their  precise  character.  I  believe  the 
impurities  of  the  mother  liquor  consist  chiefly  of  disulphate  of 
quinidia,  and  of  neutral  sulphates  of  quinidia  and  quinia.  The 
last  two  salts  contain,  respectively,  12  and  16  equivalents  of  water 
of  crystallization,  and  when  dried  at  212°,  lose,  respectively,  19 
and  24  per  cent,  of  water.    (Pereira,  vol.  2,  pp.  672  and  674.) 
I  have  very  recently  noticed  that  in  the  translation  of  Witt- 
stein's  Practical  Pharmaceutical  Chemistry,  the  composition  of 
crystallized  disulphate  of  quinia  is  given  as  containing  10  eq.  of 
water,  the  points  of  solubility  and  reactions  common  to  other 
authorities  being  retained.  Whilst  "  Ch.  Linck  has  found  (Lie- 
big  &  Kopp's  Annual  Report,  1850,  vol.  4.  p.  284,)  that  the 
sulphate  of  quinia  of  commerce  possesses  the  formula,  2C20  H12 
N02,  HO,  SO?,  +  4HO,  (9.8  per  cent,  of  sulphuric  acid,  and  8.4 
per  cent,  of  water  of  crystallization)  the  4  equivs.  HO  escape  at 
130°,"  (266°  F.  ?) 
In  reply  to  your  editorial  remark,  I  cannot  undertake  to  ex- 
amine the  sulphate  of  quinia  of  any  other  manufacturers  until  I 
have  occasion  to  use  their  preparations,  for  I  have  not  the  time 
allotted  to  me  to  study  the  interests  of  Pharmacy  farther  than 
they  are  immediately  connected  with  my  present  duties.  Should 
I  have  made  such  examinations,  however,  and  have  found  the 
preparation  of  Messrs.  Powers  &  Weightman  preferable  to  all 
others,  it  could  not  certainly  change  my  belief  that  in  this  best 
preparation  there  is  room  for  much  improvement.  It  is  the 
cause  and  interests  of  medicine  and  pharmacy  that  I  wish  to 
defend  ;  for  if  it  was  the  interests  of  Manufacturers  that  I 
wished  to  attack,  there  are  many,  doubtless,  more  vulnerable  than 
those  of  Messrs.  Powers  &  Weightman. 
Very  respectfully, 
Your  obed't  serv't. 
E.  R.  Squibb. 
V.  S.  Naval  Laboratory,  New  York,  September  24,  1855. 
