Am.  Jour.  Pharm. 
Jan.,  1886. 
Preparation  of  Amyl  Nitrite. 
37 
allowed  to  mix,  taking  the  precaution  to  keep  the  gas  evolved  from  the 
nitrite  of  sodium  in  considerable  excess.  The  mixed  gases  were  passed 
into  amyl  alcohol  kept  cool  as  usual.  There  was  no  excessive  tendency 
to  heat  up.    Much  gas  was  absorbed,  but  of  course  some  passed  through 
unabsorbed.    The  washed  product  distilled  gave — 
10  per  cent,  under   90°  C. 
87      "         "  100°  C. 
93      "         "  105°  C. 
This  result  being  promising  the  experiment  was  repeated  with  per- 
haps greater  care,  and  taking  special  precautions  to  keep  the  nitrogen 
binoxide  in  excess.    The  result  obtained  was — 
9  percent,  under   90°  C. 
95      "         "     •  •  •  100°  C. 
This  being  the  best  result  as  yet  obtained. 
Experiment  No.  6. — The  experiment  just  detailed  (No.  5)  was  re- 
peated, with  certain  modifications;  in  place  of  the  nitrite  of  sodium  and 
nitric  acid,  to  produce  the  N02,  copper  turnings  and  nitric  acid  were 
used,  and  the  arsenious  acid  was  acted  upon  by  nitric  acid  of  sp.  gr. 
1520,  or  the  very  strongest  commercial  article.  We  found  it  necessary 
to  use  the  arsenious  acid  in  lumps,  otherwise  the  action  became  so  vio- 
lent as  to  endanger  the  apparatus.  In  this  experiment  great  care  was 
taken  to  keep  the  nitrogen  peroxide  gas  evolved  from  the  copper  turning 
and  nitric  acid  in  large  excess.    The  result  obtained  was — 
12  percent,  distilling  under   90°  C. 
95      "  "  "   100°  C. 
97      "  "  "  105°  C. 
This  leaving  three  parts  only  unaccounted  for.  We  need  hardly  say 
this  result  was  considered  as  perfect  as  could  be  expected. 
As  a  general  result  we  think  these  experiments  show  that  amyl 
alcohol  can  be  usefully  employed  to  determine,  at  any  rate  to  some 
extent,  the  nature  of  the  gases  evolved  by  the  action  of  nitric  acid  of 
various  strengths  upon  arsenious  acid. 
In  experiment  1,  where  nitric  acid  of  sp.  gr.  1500  was  used,  we 
suppose  there  can  be  no  doubt  that  the  gas  evolved  was  very  nearly 
pure  nitrogen  tetroxide  (N204).  It  is  stated  in  chemical  works  that 
this  gas  acting  upon  amyl  alcohol  is  broken  up  into  nitrous  acid  N2Os 
and  nitric  acid.  The  nitrous  acid  naturally  produces  some  nitrite  of 
amyl,  and  in  our  experiment  the  quantity  found  appears  to  be  only  42 
per  -cent.    What  other  products  are  obtained  by  the  action  of  the  nitric 
