SPIRITUS  iETHERIS  NITROSI. 
541 
a  conducting  tube ;  a  Liebig's  condenser,  two  and  a  half  inches 
long,  made  of  ordinary  sheet  tin,  painted,  to  keep  it  from  rust- 
ing— the  internal  tube  of  glass,  three-quarters  inch  in  diameter, 
and  at  its  lower  extremity  drawn  to  a  point,  so  as  to  enter  the  re- 
ceiving bottle-;  an  ordinary  pint  packing  bottle  ;  a  reservoir  of 
ice-water,  fitted  with  a  stop-cock  ;  a  retort  stand  ;  a  lamp. 
The  Process.— No.  1.  Take  of  Alcohol  (sp.  gr.  835)  a 
sufficient  quantity;  stronger  alcohol,  eight  fluidounces;  nitric 
acid  (sp.  gr.  1*42),  six  fluidounces  ;  carbonate  of  potassa,  half  a 
troy  ounce.  Or  if  nitric  acid  sp.  gr.  1*42  can  not  be  obtained, 
then  take  of — 
No.  2.  Alcohol  (sp.  gr.  853)  a  sufficient  quantity ;  stronger 
alcohol,  twenty-one  fluidounces  ;  commercial  nitric  acid  (sp.  gr. 
1*36),  seven  fluidounces ;  carbonate  of  potassa,  half  a  troy 
ounce. 
Introduce  into  the  generating  bottle,  with  a  Utile  clean  sand, 
thirteen  fluidounces  of  alcohol,  sp.  pr.  835,  if  formula  No.  1 — 
stronger  alcohol  if  formula  No.  2  is  used— and  three  fluidounces 
of  the  nitric  acid.  Having  filled  the  safety  tube  with  nitric  acid, 
and  otherwise  properly  adjusted  the  apparatus,  apply  heat.  As 
soon  as  the  reaction  is  fairly  established,  withdraw  the  water 
from  the  bath,  and  allow  the  reaction  to  proceed  spontaneously, 
which  it  does  to  the  end,  care  being  taken  to  add  the  remainder 
of  the  acid  through  the  safety  tube  in  small  portions,  only,  at  a 
time,  and  at  such  intervals  as  to  maintain  the  reaction  in  mod- 
erate activity.  Distillation  having  ceased,  remove  the  distillate 
(nearly  ten  fluidounces),  and  add  to  it  first  the  carbonate  of 
potassa,  and  then  twice  its  volume  of  water.  The  mixture 
having  been  well  shaken,  by  means  of  a  separating  funnel,  sepa- 
rate the  supernatant  ether  (about  five  fluidounces),  and  add  to  it 
eight  fluidounces  stronger  alcohol,  and  sufficient  alcohol  (sp.  gr. 
835)  to  make  the  measure  up  to  one  hundred  fluidounces,  or  to 
such  a  point  that  the  finished  product  will  correspond,  in  ethereal 
strength,  to  that  indicated  b*y  the  U.  S.  Pharmacopoeia.  Finally, 
preserve  the  spirit  in  well  stopped  bottles. 
Although,  as  before  stated,  a  thermometer  is  not  necessary  to 
the  practical  success  of  the  operation,  the  observation  of  the 
thermometric  changes  occurring  during  the  process  is  instructive, 
