506  Spiritus  Mtheris  Nitrosi.  {^o™/^*™' 
the  alcohol  of  the  distillate,  and  certainly  most  if  not  all  the  aldehyc? 
and  possibly  other  products.  With  the  hope  of  utilizing  the  washings 
and  recovering  alcohol  or  ether,  I  have  redistilled  them  with  lime  and 
filtered  through  charcoal,  but  it  is  bad  smelling,  ultimately  goes  yellow, 
and  is  best  out  of  good  spt.  nitre,  though  not  worse  than  much  that  is 
sold.  The  main  difficulty  of  this  process  is  the  volatile  character  of 
the  ether,  rendering  the  separation  by  a  syphon  a  somewhat  risky- 
process,  and  giving,  if  inhaled,  a  most  cadaverous  hue  to  the  operator. 
Great  care  has  also  to  be  taken  when  the  water  and  lime  are  added  to 
keep  all  very  cold,  as  the  mixture  with  the  spirituous  liquid  generates 
heat  enough  to  make  the  ether  boil.  With  these  precautions  the  process 
is  not  more  than  ordinarily  difficult.  One  ounce  of  the  ether  with  a 
pint  of  spirit  makes  nitre  of  5  per  cent,  strength  ;  two  ounces  10  per 
cent,  or  B.P.  strength,  as  Mr.  Rimmington  has  pointed  out.  The  5 
per  cent,  is,  I  think,  strong  enough  for  medicinal  purposes,  and  would 
generally  be  preferred. 
In  conclusion,  I  beg  to  say  that  whether  this  is  the  spt.  nitre  that  is 
to  be,  or  not,  it  has  much  to  recommed  it.  It  has  a  beautiful  sweet 
flavor,  something  like  chloroform,  and  I  believe  is  free  from  aldehyd 
and  other  noxious  products — Phar.  "Jour,  and  Trans.,  July  12,  1879. 
SPIRITUS  iETHERIS  NITROSI-ITS  COMPOSITION  AND 
ANALYSIS. 
By  F.  M.  Rimmington,  F.C.S. 
The  nature,  substance  and  quality  of  spiritus  aetheris  nitrosi  has 
long  been  a  problem  asking  for  solution  ;  and  as  I  have  given  a  good 
deal  of  attention  to  it  for  a  long  time,  and  feel  myself  under  a  pledge 
to  contribute  another  paper  on  the  question  raised  some  time  ago  as  to 
the  actual  existence  of  nitrite  of  ethyl  in  this  compound,  I  now  pur- 
pose fulfilling  that  promise. 
Perhaps  some  discriminating  minds  will  draw  a  distinction  between 
sweet  spirit  of  nitre  and  spiritus  aetheris  nitrosi.  I  make  no  such  dis- 
tinction, and  all  that  is  said  in  this  paper  has  reference  to  a  spirit  that 
corresponds  with  that  described  in  the  British  Pharmacopoeia,  in  nature,, 
substance  and  quality. 
I  think  all  who  have  attempted  the  analytical  examination  of  this 
preparation  will  admit  it  is  surrounded  with  some  difficulty. 
