﻿406 
  MR 
  HENRY 
  HOW 
  ON 
  MECONIC 
  ACID, 
  

  

  pears 
  after 
  some 
  little 
  time. 
  On 
  evaporating 
  the 
  liquid 
  which 
  has 
  ceased 
  to 
  give 
  

   deposits 
  to 
  complete 
  dryness, 
  the 
  chief 
  constituent 
  of 
  the 
  residue 
  is 
  found 
  to 
  be 
  

   a 
  substance 
  fusing 
  under 
  boiling 
  water 
  ; 
  it 
  is 
  more 
  or 
  less 
  accompanied 
  by 
  the 
  

   other 
  bodies 
  according 
  to 
  the 
  said 
  conditions. 
  

  

  Ethylomeconic 
  Acid. 
  

  

  The 
  first 
  deposit 
  I 
  have 
  usually 
  found 
  to 
  be 
  so 
  nearly 
  a 
  pure 
  and 
  uniform 
  sub- 
  

   stance, 
  that 
  one 
  recry 
  stall 
  isation 
  from 
  hot 
  water, 
  after 
  a 
  little 
  washing, 
  was 
  suf- 
  

   ficient 
  to 
  render 
  it 
  completely 
  so 
  ; 
  it 
  then 
  appeared 
  as 
  highly 
  crystalline 
  in 
  bril- 
  

   liant 
  short 
  needles. 
  The 
  following 
  is 
  its 
  analysis 
  : 
  — 
  

  

  {5*500 
  grains, 
  air-dry, 
  gave 
  

   9-558 
  ... 
  carbonic 
  acid, 
  and 
  

   1-860 
  ... 
  water. 
  

  

  {5-110 
  grains, 
  dried 
  in 
  vacuo, 
  gave 
  

   8830 
  ... 
  cai'bonic 
  acid, 
  and 
  

   1685 
  ... 
  water. 
  

  

  Calculation. 
  

  

  

  I. 
  

  

  II. 
  

  

  

  Carbon, 
  

  

  . 
  47-39 
  

  

  47-12 
  

  

  4736 
  

  

  Hydrogen, 
  

  

  3-75 
  

  

  3-66 
  

  

  3-50 
  

  

  Oxygen, 
  

  

  • 
  

  

  ... 
  

  

  49-14 
  

  

  C 
  18 
  108 
  

   H 
  8 
  8 
  

  

  °u 
  112 
  

  

  100-00 
  100-00 
  100-00 
  228 
  

  

  from 
  which 
  it 
  is 
  obvious 
  that 
  we 
  have 
  here 
  an 
  acid 
  ether, 
  analogous 
  to 
  phospho- 
  

   vinic 
  acid, 
  in 
  which 
  one 
  atom 
  of 
  water 
  of 
  a 
  tribasic 
  acid 
  is 
  replaced 
  by 
  an 
  equiva- 
  

   lent 
  of 
  ether 
  ; 
  its 
  rational 
  formula 
  is, 
  therefore, 
  

  

  2 
  HO, 
  C 
  4 
  H 
  6 
  C 
  14 
  HO 
  u 
  , 
  

  

  according 
  to 
  which 
  it 
  is 
  a 
  bibasic 
  acid 
  : 
  this 
  I 
  shall 
  presently 
  shew 
  to 
  be 
  the 
  case. 
  

   I 
  propose 
  to 
  call 
  this 
  the 
  ethylomeconic 
  acid, 
  in 
  preference 
  to 
  meconovinic 
  acid, 
  

   both 
  as 
  more 
  expressive 
  of 
  one 
  of 
  its 
  constituents, 
  and 
  to 
  facilitate 
  its 
  comparison 
  

   with 
  another 
  ether, 
  to 
  be 
  described 
  shortly, 
  which 
  I 
  should 
  hardly 
  know 
  how 
  to 
  

   name 
  otherwise 
  than 
  by 
  calling 
  biethylomeconic 
  acid, 
  containing, 
  as 
  it 
  does, 
  two 
  

   equivalents 
  of 
  ether. 
  

  

  Ethylomeconic 
  acid, 
  when 
  pure, 
  crystallises 
  from 
  boiling 
  water 
  in 
  brilliant 
  

   small 
  crystals, 
  which, 
  when 
  magnified, 
  are 
  seen 
  to 
  be 
  square 
  prismatic 
  needles. 
  

   It 
  is 
  very 
  readily 
  soluble 
  in 
  this 
  menstruum, 
  also 
  in 
  ether 
  and 
  common 
  alcohol 
  

   when 
  warmed, 
  less 
  soluble 
  in 
  absolute 
  alcohol. 
  It 
  separates 
  from 
  concentrated 
  

   solutions 
  in 
  these 
  three 
  fluids 
  in 
  groups 
  of 
  stellate 
  crystals, 
  and 
  when 
  they 
  are 
  

   left 
  to 
  spontaneous 
  evaporation, 
  in 
  long 
  needles. 
  It 
  is 
  anhydrous, 
  its 
  crystals 
  lose 
  

   no 
  weight 
  either 
  in 
  vacuo 
  or 
  at 
  212° 
  Fahr. 
  It 
  fuses 
  at 
  about 
  316°-318° 
  Fahr. 
  to 
  

   a 
  transparent 
  yellowish 
  liquid, 
  with 
  the 
  formation 
  of 
  a 
  sublimate 
  in 
  very 
  bril- 
  

   liant 
  rhombic 
  crystals. 
  

  

  