﻿296 
  Messrs. 
  J. 
  G. 
  M'Kendrick 
  and 
  J. 
  Dewar 
  on 
  

  

  4. 
  Collidine, 
  C 
  8 
  H 
  n 
  N. 
  

   Collidiue 
  was 
  still 
  more 
  active 
  in 
  its 
  effects. 
  "With 
  a 
  dose 
  of 
  \\ 
  grain 
  

   per 
  pound 
  weight, 
  the 
  animal 
  rapidly 
  sank 
  into 
  a 
  state 
  of 
  profound 
  

   stupor, 
  *from 
  which 
  it 
  could 
  not 
  be 
  aroused. 
  Anaesthesia 
  was 
  complete. 
  

   The 
  pulsations 
  of 
  the 
  heart 
  and 
  the 
  respirations 
  became 
  more 
  and 
  more 
  

   feeble, 
  until 
  death 
  ensued 
  in 
  about 
  20 
  minutes 
  after 
  the 
  dose, 
  apparently 
  

   in 
  consequence 
  of 
  failure 
  of 
  respiration. 
  There 
  were 
  no 
  twitchings 
  or 
  

   convulsions. 
  The 
  subcutaneous 
  injection 
  into 
  a 
  rabbit 
  of 
  l-80th 
  of 
  a 
  

   grain 
  of 
  strychnine 
  was 
  followed 
  by 
  the 
  usual 
  physiological 
  effects 
  of 
  that 
  

   substance. 
  

  

  5. 
  The 
  Higher 
  Pyridine 
  Bases 
  obtained 
  by 
  distillation 
  above 
  200° 
  0., 
  

   such 
  as 
  Parvoline, 
  C 
  9 
  H 
  13 
  N, 
  &c. 
  

  

  These 
  were 
  found 
  to 
  be 
  still 
  more 
  active 
  ; 
  but 
  the 
  effects 
  were 
  of 
  the 
  

   same 
  nature 
  as 
  those 
  just 
  described. 
  The 
  lethal 
  dose 
  was 
  found 
  to 
  be 
  

   about 
  I 
  of 
  a 
  grain 
  per 
  pound 
  weight. 
  In 
  two 
  or 
  three 
  minutes 
  the 
  animal 
  

   sank 
  on 
  its 
  abdomen 
  ; 
  when 
  pushed 
  could 
  move 
  with 
  difficulty 
  ; 
  respira- 
  

   tions 
  were 
  rapid 
  and 
  irregular. 
  It 
  then 
  lay 
  on 
  its 
  side, 
  and 
  in 
  four 
  or 
  

   five 
  minutes 
  died, 
  apparently 
  in 
  an 
  asphyxiated 
  condition. 
  There 
  were 
  

   no 
  convulsive 
  spasms 
  or 
  twitchings. 
  This 
  substance 
  was 
  lethal 
  in 
  much 
  

   smaller 
  doses 
  than 
  the 
  lower 
  bases 
  of 
  the 
  chinoline 
  series. 
  

  

  The 
  pyridine 
  series 
  of 
  compounds 
  thus 
  showed 
  a 
  gradual 
  increase 
  in 
  

   activity 
  of 
  physiological 
  action. 
  The 
  lowest 
  of 
  the 
  series 
  produced 
  

   merely 
  excitement 
  from 
  irritation 
  of 
  the 
  encephalic 
  nervous 
  centres, 
  while 
  

   the 
  highest 
  produced 
  paralysis 
  of 
  these 
  nervous 
  centres. 
  There 
  was 
  no 
  

   irritation 
  of 
  the 
  spinal 
  cord 
  causing; 
  increased 
  reflex 
  activity. 
  Death 
  

   ensued 
  from 
  gradual 
  failure 
  of 
  the 
  respiratory 
  movements 
  leading 
  to 
  

   asphyxia. 
  The 
  action 
  of 
  the 
  higher 
  pyridines 
  was 
  thus 
  somewhat 
  analo- 
  

   gous 
  to 
  the 
  lowest 
  of 
  the 
  chinoline 
  series, 
  with 
  this 
  exception, 
  that 
  the 
  

   pyridine 
  compounds 
  tended 
  to 
  cause 
  death 
  by 
  asphyxia. 
  It 
  is 
  to 
  be 
  

   noted 
  also 
  that 
  the 
  higher 
  bases 
  of 
  the 
  pyridine 
  series 
  were 
  lethal 
  in 
  

   somewhat 
  less 
  than 
  one 
  half 
  of 
  the 
  dose 
  required 
  to 
  destroy 
  life 
  by 
  the 
  

   lower 
  members 
  of 
  the 
  chinoline 
  series. 
  

  

  V. 
  Action 
  of 
  Hydrochlorates 
  of 
  the 
  condensed 
  Bases 
  of 
  the 
  

   Pyridine 
  Series. 
  

  

  Considering 
  the 
  close 
  analogy 
  in 
  chemical 
  composition 
  between 
  the 
  

   polymeric 
  bases 
  of 
  pyridine 
  and 
  certain 
  natural 
  bases, 
  such 
  as 
  nicotine, 
  

   it 
  became 
  of 
  importance 
  to 
  examine 
  the 
  physiological 
  action 
  of 
  these 
  

   bases, 
  which 
  were 
  prepared, 
  according 
  to 
  Anderson's 
  method, 
  by 
  the 
  

   action 
  of 
  sodium 
  on 
  pyridine, 
  picoline, 
  &c. 
  The 
  following 
  were 
  the 
  

   effects 
  observed 
  after 
  the 
  subcutaneous 
  injection 
  of 
  1 
  grain 
  per 
  pound 
  

   weight 
  into 
  a 
  rabbit 
  : 
  — 
  The 
  animal 
  remained 
  quiet 
  for 
  a 
  period 
  varying 
  

   from 
  four 
  to 
  eight 
  minutes, 
  when 
  it 
  suddenly 
  appeared 
  uneasy, 
  ran 
  for- 
  

   wards 
  as 
  on 
  tiptoe, 
  with 
  the 
  back 
  arched, 
  and, 
  falling 
  on 
  its 
  side, 
  became 
  

  

  