AMERICAN  PHARMACEUTICAL  ASSOCIATION.  493 
28.  Spirit  of  nitrous  ether  varies  greatly  as  obtained  from  different 
manufacturers.  By  what  practical  process  may  the  proportion  of  nitrous 
ether  in  the  spirit  be  estimated,  and  is  the  alcoholic  strength  of  the  U.  S. 
Pharmacopoeia  a  proper  one  ?  Accepted  hy  F»  Mahla,  of  Chicago. 
29.  The  aromatic  sulphuric  acid  of  the  United  States  Pharmacopoeia 
is  objectionable  in  that  it  deposits  upon  standing,  and  when  diluted  with 
water,  resinous  and  coloring  matter  separates.  How  can  the  formula  be 
medified  to  overcome  these  objections  ? 
Accepted  hy  Thomas  DoUber,  of  Boston. 
30.  Medicated  and  aromatic  waters,  prepared  by  rubbing  essential  oils 
with  carbonate  of  magnesia,  are  found  to  contain  soluble  salts  derived 
from  the  magnesia.  What  substance  can  be  substituted  for  the  magnesia 
that  will  furnish  a  water  free  from  foreign  matter  ? 
Accepted  by  S.  A.  D.  Shepard,  of  Boston,  Mass. 
31.  What  proportion  of  magnesia  is  contained  in  the  solution  of  citrate 
of  magnesia  as  obtained  from  dififerent  sources,  and  how  do  these  solu- 
tions diflfer  from  the  officinal? 
Accepted  hy  Prof  Geo.  F.  H.  MarJcoe  of  Boston,  Mass. 
32.  In  what  respect  does  deodorized  tincture  of  opium  differ  from  the 
elixirs  of  opium  in  the  market?  The  former  prepared  by  the  U.  S. 
Pharm.  process  gradually  deposits  a  dark  colored  sediment.  Are  any  of 
the  active  principles  thrown  down  in  connection  with  the  deposit? 
Accepted  by  Charles  E.  Dohme,  of  Baltimore,  Md. 
33.  What  is  the  comparative  value  of  carbolic  acid  and  other  disinfect- 
ants and  antiseptics  ?    Which  is  the  best  disinfectant  for  general  use  ? 
Accepted  by  Edward  C.  Jones,  of  Philadelphia. 
34.  Prof.  Wormly  has  isolated  two  active  principles  from  yellow  jasmin 
[Gelsemium  sempervirens),  one  of  which  he  calls  gelsemine,  and  the  other 
gelseminic  acid.  How  may  these  principles  be  isolated  in  quantity? 
What  is  the  antidote  to  the  poisonoas  effects  of  this  drug? 
Accepted  by  Joseph  M.  Hirsh,  of  Chicago. 
35.  Is  the  ordinary  commercial  alcohol  of  the  market  sufficiently  free 
from  fusel  or  grain  oil  for  pharmaceutical  use  ? 
Accepted  by  N.  Pierpoint,  of  Young  America,  Illinois. 
36.  It  is  found  that  ordinary  menstrua  do  not  hold  polygalic  acid  of 
senega  in  solution,  and  that  well  made  fluid  extracts  of  senega  from  good 
specimens  of  the  drug  are  liable  to  gelatinize  in  cold  weather.  What 
menstruum  is  best  adapted  for  holding  all  the  active  principles  of  senega 
in  permanent  solution,  and  excluding  pectin  and  other  useless  substances  ? 
Accepted  by  H.  N.  Rittenhouse,  of  Philadelphia. 
37.  What  is  the  best  formula  for  solution  of  citrate  of  magnesia  ?  Can 
a  permanent  solution  of  it  be  made? 
Accepted  hy  E.  H.  Sargent,  of  Chicago. 
