Am  ja°nufiSo"m'}  Physiological  Action  of  Salicylic  Acid.  41 
were  dissolved  in  twenty  minims  of  rectified  spirit  and  injected  into 
a  rabbit,  which  weighed  one  and  a  half  pounds.  Within  fifteen 
minutes  the  animal  assumed  a  prone  position,  with  its  hind  legs 
stretched  out.1  In  the  course  of  half  an  hour  the  breathing  became 
labored  and  there  was  also  great  prostration,  as  evidenced  by  the 
head  resting  between  the  fore-limbs  and  inability  to  move.  In  the 
evening  the  hind-limbs  were  completely  paralyzed,  and  in  thirty 
hours  from  the  time  of  the  injection  being  given  the  animal  died. 
P-acid.  On  the  same  day  and  at  the  same  time  two  grains  of 
this  sample  similarly  dissolved  were  injected  into  a  rabbit  also 
weighing  one  and  a  half  pounds.  In  the  course  of  thirty  minutes 
slight  symptoms  of  prostration  were  evinced,  but  it  was  found  that 
these  were  not  so  severe  as  in  the  previous  case,  for  when  roused 
the  animal  could  move  about  fairly  well.  Yet  it  was  observed  that 
the  animal  was  under  the  influence  of  a  poison  by  its  refusing  to  take 
food  and  by  the  peaked  expression  of  its  face.  On  the  morning  of 
the  10th  it  was  found  dead,  having  lived  twelve  hours  longer  than 
the  rabbit  which  had  received  the  injection  of  ortho-cresotic  acid. 
Artificial  Salicylic  Acid. — This  acid  was  slowly  crystallized  from 
solutions  in  boiling  water,  and  as  the  result  of  this  procedure  the 
crystals  became  better  defined.  On  October  28th  ten  grains  dis- 
solved in  rectified  spirit  were  injected  into  a  rabbit  weighing  three 
pounds.  Another  specimen  of  the  purified  artificial  acid  from 
Professor  Dunstan  in  larger  crystals  also  afforded  a  satisfactory 
result. 
M-acid. — November  1,  1890.  Two  grains  of  this  sample  dissolved 
in  rectified  spirit  were  injected  into  a  rabbit  weighing  one  and  a 
half  pounds.  In  this  instance  there  was  not  the  slightest  evidence 
of  any  unhealthy  action. 
Summary. — The  ortho-  and  para-cresotic  acids  by  their  physiologi- 
cal action  show  that  they  are  slow  but  certain  poisons,  causing  pros- 
tration and  paralysis  affecting  first  the  hind  limbs  and  gradually 
extending  over  the  body.  The  lethal  dose  is  about  I  grain  for  a 
pound  rabbit.  These  facts,  now  corroborated,  were  mentioned  in 
the  article  which  appeared  in  the  British  Medical  Journal,  Novem- 
1  The  mode  of  injection  in  this  and  the  following  experiments  may  be 
stated.  An  assistant  held  the  rabbit  on  its  back.  A  piece  of  skin  was  picked 
up  from  the  abdominal  wall — the  hypodermic  needle  was  then  inserted  and 
the  contents  of  the  syringe  slowly  pressed  out.  . 
