386 
Spirit  of  Nitrous  Ether. 
/Am.  Jour.  Pharm. 
1       July, 1884. 
"  With  regard  to  aldehyde,  I  cannot  at  the  present  moment  recall 
having  seen  any  notice  of  its  physiological  action.  I  rather  think  it  has 
not  to  any  extent  been  investigated.  But  although  that  is  probably 
so,  I  am  fairly  certain,  judging  from  its  chemical  relationship  to 
alcohol  and  the  ethers,  that  in  action  it  will  differ  to  no  great  extent 
from  these." 
"  With  regard  to  the  sweet  spirit  of  nitre,  my  opinion  is  this,  that 
its  most  active  ingredient  ought  to  be  the  nitrite  of  ethyl,  which  it  is 
believed  to  contain,  to,  I  think,  the  extent  of  2  per  cent.  But  so  far 
as  my  observation  carries  me,  nitrite  of  ethyl  is  present  in  very 
variable  quantity  in  the  ordinary  spirit  of  nitrous  ether,  and  is  some- 
times hardly  to  be  detected  at  all.  The  nitrite  is  very  active  even  in 
very  small  quantity  ;  and,  I  believe  that  if  a  preparation  of  spirit,  aeth. 
nit.  could  be  obtained  containing  a  constant  proportion  of  nitrite  of 
ethyl,  it  would  be  a  great  gain  to  practical  pharmacy  and  to  thera- 
peutics. The  unreliability  of  the  common  forms  of  it  has,  I  believe,  led 
largely  in  recent  years  to  its  disuse." 
"  Murrell  states  that  nitroglycerin  is  powerfully  diuretic,  and  I  have 
shown  that  nitroglycerin  is  decomposed  into  nitrite  in  blood,  hence  its 
physiological  action — hence  diuresis." 
I  am  glad  to  have  my  own  opinion  confirmed  by  so  eminent  an  au- 
thority. We  may,  therefore,  conclude  that  the  right  means  of  estimat- 
ing a  sample  of  spirits  of  nitre  is  to  determine  the  amount  of  nitrous 
ether,  or  rather,  of  nitrous  acid,  which  it  contains.  I  am  far  from 
denying  that  the  medicinal  value  of  the  spirit  may  be  materially  en- 
hanced by  the  aldehyde  and  acetic  ether,  but  these  may  be  regarded 
as  quite  subordinate.    Besides,  it  is  difficult  to  estimate  their  amount. 
Let  us  now  consider,  one  by  one,  the*  tests  of  the  British  Phar- 
macopoeia. Firstly,  we  have  the  specific  gravity,  which  is  given  as 
•845,  at  60°  F.  This  is  really  only  a  safeguard  "against  admixture 
with  water,  though  there  is  a  delusion,  still  to  some  extent  prevalent, 
that  the  '850  must  be  a  better  article  than  the  '845.  Doubtless  this 
has  arisen  from  the  fact  that  nitrous  ether  has  a  greater  density  than 
rectified  spirit.  It  has  therefore  been  supposed  that  a  preparation  rich 
in  nitrous  ether  will  have  a  high  specific  gravity,  but  this  is  a  mistake ; 
for  it  is  easy  to  prepare  a  spirit  fully  up  to  the  Pharmacopoeia  require- 
ments with  a  specific  gravity  even  less  than  *845.  According  to  our 
experience  a  high  specific  gravity  just  means  so  much  the  more  water, 
and  if  one  fact  regarding  spirit  of  nitre  has  been  proved  more  con- 
