Am  Jour.  Pharm. 
Oct.,  1887. 
Ethyl  Nitrite. 
487 
The  ether  decanted  from  the  carbonate  of  potassium  was  poured  into 
a  small  Wurtz  fractional  distillation  flask,  with  a  plain  neck,  around 
which  was  wrapped  several  thicknesses  of  paper;  the  flask  was  now 
connected  to  a  condenser  and  fitted  with  a  caoutchouc  stopper,  through 
which  a  thermometer  passed  into  the  liquid.  In  the  final  determina- 
tions, which  represent  some  fifty  or  more,  a  Geissler  standard  thermo- 
meter was  used. 
The  heat  applied  was  very  gentle,  using  the  palm  of  the  hand, 
while  the  temperature  of  the  room  in  no  case  was  above  +  12°  C, 
and  in  the  greater  number  of  determinations  was  from  -f-  3°  to  -j-  4°  C. 
At  first,  the  boiling  point  was  secured  by  allowing  the  liquid  to 
boil  thoroughly,  then  allowing  it  to  cool,  and  again  boiling,  during 
which  the  bulb  of  the  thermometer  was  alternately  raised  to  one-half 
inch  below  the  orifice  of  the  exit  tube  and  again  lowered  into  the 
liquid  j  this  was  to  see  whether  the  boiling  liquid  and  its  vapor  were 
of  the  same  temperature.  In  the  majority  of  instances  they  were  the 
same,  while  in  a  few  only  was  there  an  advance  of  one-tenth  of  a 
degree  in  the  boiling  liquid.  The  readings  were  made  as  rapidly  as 
possible  and  with  a  magnifying  glass.  The  barometric  pressure  was 
also  carefully  noted. 
Ethyl  nitrite  prepared  according  to  one,  four  and  five  were  tried  in 
this  manner. 
Ethyl  nitrite  after  No.  1,  gave  in  the  preliminary  a  boiling  point 
of  16.5°  C,  whilst  that- from  Carey  Lea's  method  gave  17°  C.  The 
mean  average  of  all  the  determinations  was  17°  C.  This  comprises 
about  seventy  trials. 
To  conclude  the  boiling  point  determinations,  some  six  ounces  of 
freshly-made  Liebig's  ethyl-nitrite  was  subjected  to  fractional  distilla- 
tion. 
The  apparatus  consisted  of  a  Wurtz  flask  connected  by  an  adapter 
to  a  Mohr's  worm,  which  was  surrounded  with  a  freezing  mixture. 
The  heat,  which  was  very  gently  applied  to  the  flask,  was  sufficient  to 
keep  the  liquid  in  a  state  of  constant  ebullition  ;  with  the  thermome- 
ter in  the  liquid  the  same  began  boiling  at  13*3°  C,  when  the  boiling 
continued  vigorously  up  to  16 '3°.  It  required  eight  minutes  to 
reach  this  temperature,  and  one  and  a  half  drachms  of  liquid  were 
obtained. 
The  thermometer  was  now  raised  until  the  bulb  was  half  an  inch 
below  the  opening  of  the  exit  tube;  it  required  fifteen  minutes  to 
