﻿the 
  Action 
  of 
  the 
  Chinoline 
  and 
  Pyridine 
  Bases. 
  297 
  

  

  violently 
  convulsed. 
  The 
  convulsions 
  continued, 
  almost 
  without 
  intermis- 
  

   sion, 
  for 
  three 
  or 
  four 
  minutes, 
  when 
  death 
  ensued. 
  So 
  far 
  as 
  could 
  be 
  

   observed, 
  consciousness 
  was 
  not 
  lost 
  until 
  immediately 
  before 
  death. 
  The 
  

   character 
  of 
  the 
  convulsions 
  resembled 
  that 
  of 
  those 
  produced 
  by 
  cinchonine 
  

   or 
  quinine, 
  except 
  that 
  the 
  tendency 
  to 
  backward 
  movements, 
  with 
  the 
  

   fore 
  legs 
  extended, 
  was 
  not 
  so 
  marked 
  ; 
  they 
  also 
  resembled 
  those 
  pro- 
  

   duced 
  by 
  salts 
  of 
  the 
  higher 
  members 
  of 
  the 
  chinoline 
  series, 
  but 
  they 
  

   were 
  more 
  severe 
  than 
  in 
  the 
  latter. 
  The 
  hydrochlorates 
  of 
  two 
  con- 
  

   densed 
  bases 
  of 
  this 
  kind 
  were 
  employed 
  — 
  the 
  first 
  made 
  from 
  pyridine, 
  

   and 
  the 
  other 
  from 
  picoline. 
  The 
  formulae 
  for 
  these 
  are 
  : 
  — 
  hydrochlorate 
  

   of 
  dipyridine, 
  C 
  10 
  H 
  10 
  N 
  2 
  2HC1 
  ; 
  and 
  hydrochlorate 
  of 
  dipicoline, 
  or 
  para- 
  

   picoline, 
  C 
  12 
  H 
  14 
  N 
  2 
  2HC1. 
  The 
  latter 
  was 
  found 
  to 
  be 
  the 
  more 
  active 
  

   of 
  the 
  two, 
  but 
  the 
  actions 
  were 
  identical 
  in 
  character. 
  

  

  VI. 
  GrEKERAL 
  CONCLUSIONS. 
  

  

  1. 
  There 
  is 
  a 
  marked 
  gradation 
  in 
  the 
  extent 
  of 
  physiological 
  action 
  of 
  

   the 
  members 
  of 
  the 
  pyridine 
  series 
  of 
  bases, 
  but 
  it 
  remains 
  of 
  the 
  same 
  

   kind. 
  The 
  lethal 
  dose, 
  however, 
  becomes 
  reduced 
  as 
  we 
  rise 
  from 
  the 
  

   lower 
  to 
  the 
  higher. 
  

  

  2. 
  The 
  higher 
  members 
  of 
  the 
  pyridine 
  series 
  resemble, 
  in 
  physiological 
  

   action, 
  the 
  lower 
  members 
  of 
  the 
  chinoline 
  series, 
  except 
  (1) 
  that 
  the 
  for- 
  

   mer 
  are 
  more 
  liable 
  to 
  cause 
  death 
  by 
  asphyxia, 
  and 
  (2) 
  that 
  the 
  lethal 
  

   dose 
  of 
  the 
  pyridines 
  is 
  less 
  than 
  one 
  half 
  that 
  of 
  the 
  chinolines. 
  

  

  3. 
  In 
  proceeding 
  from 
  the 
  lower 
  to 
  the 
  higher 
  members 
  of 
  the 
  chino- 
  

   line 
  series, 
  the 
  physiological 
  action 
  changes 
  in 
  character, 
  inasmuch 
  as 
  the 
  

   lower 
  members 
  appear 
  to 
  act 
  chiefly 
  on 
  the 
  sensory 
  centres 
  of 
  the 
  ence- 
  

   phalon 
  and 
  the 
  reflex 
  centres 
  of 
  the 
  spinal 
  cord, 
  destroying 
  the 
  power 
  of 
  

   voluntary 
  or 
  reflex 
  movement 
  ; 
  while 
  the 
  higher 
  act 
  less 
  on 
  these 
  centres, 
  

   and 
  chiefly 
  on 
  the 
  motor 
  centres, 
  first 
  as 
  irritants, 
  causing 
  violent 
  con- 
  

   vulsions, 
  and 
  afterwards 
  producing 
  complete 
  paralysis. 
  At 
  the 
  same 
  

   time, 
  while 
  the 
  reflex 
  activity 
  of 
  the 
  centres 
  in 
  the 
  spinal 
  cord 
  appears 
  to 
  

   be 
  so 
  far 
  inactive 
  as 
  not 
  to 
  be 
  excited 
  by 
  pinching 
  or 
  pricking, 
  it 
  may 
  be 
  

   readily 
  roused 
  to 
  action 
  by 
  strychnine. 
  

  

  4. 
  On 
  comparing 
  the 
  action 
  of 
  such 
  bases 
  as 
  C 
  9 
  H 
  7 
  N 
  (chinoline) 
  with 
  

   C 
  9 
  H 
  13 
  N 
  (parvoline), 
  or 
  C 
  8 
  H 
  u 
  N 
  (collidine) 
  with 
  C 
  8 
  H 
  15 
  N 
  (conia 
  from 
  

   hemlock), 
  or 
  C 
  i0 
  H 
  10 
  N 
  2 
  (dipyridine) 
  with 
  C 
  10 
  H 
  14 
  N 
  2 
  (nicotine 
  from 
  to- 
  

   bacco), 
  it 
  is 
  to 
  be 
  observed 
  that, 
  apart 
  from 
  differences 
  in 
  chemical 
  struc- 
  

   ture, 
  the 
  physiological 
  activity 
  of 
  the 
  substance 
  is 
  greater 
  in 
  those 
  bases 
  

   containing 
  the 
  larger 
  amount 
  of 
  hydrogen. 
  

  

  5. 
  Those 
  artificial 
  bases 
  which 
  approximately 
  approach 
  the 
  percentage 
  

   composition 
  of 
  natural 
  bases 
  are 
  much 
  weaker 
  physiologically, 
  so 
  far 
  as 
  

   can 
  be 
  estimated 
  by 
  amount 
  of 
  dose, 
  than 
  the 
  natural 
  bases 
  ; 
  but 
  the 
  kind 
  

   of 
  action 
  is 
  the 
  same 
  in 
  both 
  cases. 
  

  

  6. 
  When 
  the 
  bases 
  of 
  the 
  pyridine 
  series 
  are 
  doubled 
  by 
  condensation, 
  

   producing 
  dipyridine, 
  parapicoline, 
  &c, 
  they 
  not 
  only 
  become 
  more 
  

  

  TCL. 
  XXIH. 
  2 
  A 
  

  

  