Am.  Jour.  Pt  arm  ) 
July,  1877.  J 
Spirit  of  Nitrous  Ether. 
363 
If  we  now  apply  the  same  rule  to  the  product  of  the  l<  British  Phar- 
macopoeia," we  obtain  results  which  very  nearly  correspond  to  the 
statement  of  that  standard.  In  this  process  rectified  spirit  of  sp.  gr. 
0*838  (see  Table  B)  is  used,  while  the  finished  product  contains  10 
per  cent,  of  nitrous  ether  and  has  a  specific  gravity  of  0*845  (see 
Table  F)  : 
10  volumes  of  nitrous  ether,  sp.  gr.  0*947,  weigh  9*47  parts, 
90  volumes  of  rectified  spirit,  sp.  gr.  0  838,  weigh  75*42  parts, 
100  volumes  of  spirit  of  nitrous  ether  weigh  84  89  parts, 
indicating  a  specific  gravity  of  0*8489  ;  a  result  which  corresponds  suffi- 
ciently close  when  it  is  considered  that  the  "  British  Pharmacopoeia  " 
does  not  positively  claim  10  per  cent,  of  absolute  nitrous  ether  in  its 
preparation. 
It  is  evident  from  these  results  that  if  the  sp.  gr.  of  the  British  pre- 
paration is  correct,  that  of  the  United  States  preparation  must  be 
wrong  ;  and  this  becomes  more  apparent  when  we  review  the  increase 
in  ponderability  over  the  respective  alcohols  used  in  the  two  processes, 
as  shown  in  the  Table  G  ;  for,  while  1000  volumes  of  the  British 
product  weigh  but  7  parts  heavier  than  the  alcohol  used  for  its  prepara- 
tion, being  0*7  parts  for  each  one  per  cent,  of  nitrous  ether,  1000  vol- 
umes of  the  product  of  the  U.  S.  P.  would,  if  the  sp.  gr.  is  correctly 
stated,  weigh  20  parts  heavier  than  the  alcohol  used  for  its  preparation, 
or  4*0  parts  for  each  one  per  cent,  of  nitrous  ether  it  is  claimed  to 
contain. 
It  remained  then  to  determine  whether  any  condensation  results  on 
the  admixture  of  the  distillate  in  the  alcohol.  For  this  purpose  the 
distillate  obtained  by  the  second  experimental  distillation  was  used. 
This,  which  at  6o°  F.  measured  15  fluidounces,  and  weighed  5974*5 
grains,  was  mixed  with  17  fluidounces  of  stronger  alcohol,  sp.  gr.  0*817, 
weighing  6328*5  grains.  One  fluidounce  of  this  mixture,  at  6o°  F., 
should  weigh,  if  no  condensation  occurs,  384  5  grains,  and  by  dividing 
this  weight  by  the  weight  of  a  fluidounce  of  water  (455*669  grains) 
we  at  once  obtain  the  specific  gravity  : 
455*669  :  384*5  ::  1  :  o  843,  the  calculated  specific  gravity  of the  concentrated  spirit. 
In  order  to  reduce  the  "  concentrated  spirit  "  to  the  volume  required 
by  the  "  Pharmacopoeia,"  72  fluidounces  of  stronger  alcohol  are 
required,  or  2*34375  fluidounces  to  1  fluidounce  of  "  concentrated 
spirit."    The  weight  of  a  fluidounce  of  a  mixture  so  made  should,  at 
