Am.  Jour.  Pharm. 
June,  1896. 
The  Pharmacopceial  Standard. 
301 
dipped  into  melted  paraffine.  One  pint  was  removed  on  a  purchase 
on  January  8th ;  the  remainder  was  tested  and  kept  as  described. 
Per  Cent. 
NH3. 
(Quart  A)  On  December  11,  1895,  it  contained  10*47 
On  January  8,  1896,  it  contained  10*21  • 
On  May  6th  it  assayed   9*50 
(Quart  B)  On  December  n,  1895,  it  contained  10*47 
On  May  6,  1896,  it  contained   9*56 
These  experiments  would  demonstrate  that  spirit  of  ammonia  of 
the  aforenamed  strength,  protected  against  evaporation  as  securely 
as  before  described,  will  gradually  lose  in  strength,  even  though  the 
bottle  has  not  been  opened  (case  B),  and  the  use  of  paraffine  in 
connection  with  glass  stoppers  does  not  offer  sufficient  or  absolute 
safeguard  against  slow  evaporation  of  the  gas.  Still,  the  amount 
that  escaped  was  so  small  that  there  was  not,  at  any  time,  a  smell 
of  ammonia  noticeable  around  the  stopper,  nor  could  a  cloudiness 
be  seen  when  a  drop  of  strong  HC1  was  held  near  it. 
(6)  Aqua  Ammonia  (Ammonia  Water.) 
"An  aqueous  solution  of  ammonia  (NH3  =  17  01),  containing  10 
per  cent.,  by  weight,  of  the  gas."— U.  S.  P.,  1890. 
It  was  herein  aimed  to  ascertain:  (1)  how  much  gas  ammonia 
water  will  lose  when  insufficiently  protected  ;  (2)  how  much  it  will 
lose  under  the  opposite  conditions. 
The  percentage  herein  recorded  refers  to  grammes  of  NH3  in  100 
c.c.  of  the  fluid.    One  quart  of  ammonia  water  was  operated  upon. 
Per  Cent. 
NH3. 
On  May  17,  1895,  its  strength  was   9*46 
On  May  21st,  bottle  covered  with  paper  only   9*22 
On  May  24th,  same  8*22 
The  specimen  was  now  divided  into  two  pints  [A  and  B). 
A  was  kept  in  a  glass-stoppered  bottle,  sealed  hermetically  with 
paraffine.  B  was  kept  in  a  bottle  loosely  covered  with  a  cork, 
which  was  simply  laid  over  the  mouth  of  the  bottle. 
A.  B. 
Per  Cent.  Per  Cent. 
NH3.  NH3. 
May  24,  1895  8*22  8*22 
June  3,  1895  8*12  7'8i 
June  15,  1895    8-09  774 
August  23,  1895                                                     8-13*  6*65 
May  6,  1896  7*84  4-83 
*  Evidently  error  of  manipulation,  which,  unfortunately,  was  not  corrected. 
