PHYSIOLOGICAL  PROPERTIES  OP  NITRITE  OF  AMYLE.  267 
action  of  the  heart  rises,  the  surface  of  the  skin  becomes  red, 
and  the  face  assumes  a  bright  crimson  color.  A  little  of  the 
nitrite  was  here  placed  on  a  piece  of  bibulous  paper,  and  passed 
round  to  show  the  effect  on  the  face,  and  the  effect  was  most 
remarkable,  causing  the  faces  of  the  persons  who  smelt  the 
vapor  to  become  instantaneously  flushed.  Carried  to  an  exces- 
sive degree,  the  nitrite  excites  the  breathing,  and  produces  a 
breathlessness  like  that  caused  by  sharp  running  or  rowing.  On 
animals,  when  the  agent  is  given  in  large  quantities,  death  is 
produced.  The  author  at  first  thought  that  the  nitrite,  like 
chloroform,  would  cause  anaesthesia;  but  experiments  had 
shown  that  this  view  was  not  borne  out.  Animals  would,  it  is 
true,  lose  consciousness ;  but  when  such  a  stage  was  reached, 
great  dangers  resulted,  owing  to  the  slowness  by  which  the 
poison  was  removed  from  the  body  after  its  absorption.  On  the 
blood  the  nitrite  produces  darkness  of  color,  but  it  does  not 
materially  interfere  with  coagulation  in  the  body.  In  the  lungs 
it  excites  congestion,  and  in  the  brain  slight  congestion.  It 
causes  no  severe  spasm  and  no  sickness.  After  entering  into 
certain  other  details,  Dr.  Richardson  proceeded  to  say  that  the 
most  remarkable  effect  produced  by  the  nitrite  was  that  in  the 
lower  animals — frogs,  for  instance — it  led  to  suspended  anima- 
tion, which  could  be  maintained  for  so  long  as  nine  days  with 
perfect  after-recovery.  This  fact  was  of  curious  historical  in- 
terest. The  ancients,  especially  Theophrastus  (Paracelsus),  had 
stated  that  there  was  a  poison  which,  when  taken  one  day  would 
not  take  effect  until  some  future  day.  This  statement,  long 
considered  as  a  myth,  had  within  the  present  year  been  shown 
to  be  true  by  Dr.  Letheby,  who  had  discovered  a  poison  which 
really  produced  this  phenomenon.  In  like  manner  the  ancients 
had  an  idea  that  there  were  medicines  which  would  for  a  time 
suspend  life.  The  proceeding  of  Friar  Lawrence  in  giving  the 
distilled  liquor  to  Juliet,  was  based  on  this  old  fiction,  or  shall 
we  not  say  fact?  The  next  point  discussed  by  Dr.  Richardson 
had  reference  to  the  mode  of  action  of  this  poison.  Were  the 
effects  produced  through  the  blood,  or  by  the  nerves  direct  ? 
The  speaker  said  that  he  had  been  led  to  the  conclusion,  from 
previous  experiments,  that  all  poisons  were  brought  into  action 
through  the  blood ;  but  this  very  commonly  accepted  theory 
