284  Amy  I  Nitrite  and  Nitrous  Ether.  {Amj{^f<*arm' 
was  added  to  the  spirit  before  titrating,  or  when  the  undiluted  spirit 
N  N 
was  titrated  with  —  instead  of  _  soda,  considerably  higher  figures 
10  1  - 
were  obtained,  doubtless  through  saponification  of  the  esters.  The 
U.S. P.  test  for  limit  of  acid  in  spirit  of  nitrous  ether  is  the  addition 
of  a  crystal  of  potassium  bicarbonate,  which  must  cause  no  efferves- 
cence. No  acid  could  be  detected  in  any  of  the  samples  by  this  test. 
After  dilution  with  an  equal  volume  of  water  and  addition  of  the 
bicarbonate,  No.  2  caused  bubbles  of  gas  to  rise  from  the  surface  of 
the  crystal  slowly;  No.  3,  under  the  same  conditions,  more  rapidly. 
It  would  not  be  safe,  however,  to  depend  on  the  test  thus  performed, 
owing  to  the  rapid  decomposition  of  ethyl  nitrite  in  presence  of 
N 
water.    Titration  with  _  alkali  seems  to  be  the  most  satisfactory. 
1 
The  remarks  in  the  aldehyde  column  refer  to  the  color  of  the 
spirit  after  prolonged  contact  with  alkali,  under  the  conditions  pre- 
scribed by  the  Pharmacopoeia,  which  requires  that  the  color  should 
not  be  decidedly  brown  within  twelve  hours  after  admixture.  The 
requirements  are  therefore  fully  met  by  all  samples. 
AMYL  NITRITE. 
No. 
P.  C.  Strength  by 
U.S.P.  Method. 
P.  C.  Strength  by  Chlo- 
rate Method. 
Per  Cent,  of 
Free  Acid. 
Aldehyde. 
I 
77-2;  77-0 
S7-o;  874 
o-6 
Dark  straw  color 
2 
S67;  86-2 
0*67 
Brownish  3-ellow 
3 
i7"3;  18-8 
21  "o;  i8-9 
0*76 
Deep  yellow 
4 
827;  83-5 
93'9;  93"4 
1-36 
Dark  straw  color 
5 
79-o;  7S"4 
S5-9;  85-3 
1*12 
Deep  yellow 
Excepting  No.  3,  the  samples  are  fairly  well  in  accord  with  the 
pharmacopoeial  requirements.  This  sample  was  somewhat  lighter 
in  color  than  the  others,  and  had  a  peculiar  must}'  odor,  probably 
derived  from  the  stopper,  which  was  old  and  defective,  and  had 
been  badly  attacked  by  the  contents  of  the  bottle. 
Nos.  4  and  5  exceed  the  limit  of  acid  set  by  the  Pharmacopoeia, 
which  is  108  per  cent.,  interpreted  in  terms  of  nitrous  acid.  It  was 
found  most  convenient  to  determine  the  acidity  by  titrating  an  alco- 
N 
holic  dilution  of  the  ether  with  _  soda,  using  phenolphthalein  as 
indicator. 
