﻿AND 
  SOME 
  OF 
  ITS 
  DERIVATIVES. 
  407 
  

  

  Its 
  aqueous 
  solution 
  reacts 
  strongly 
  acid, 
  and 
  readily 
  coagulates 
  the 
  white 
  of 
  

   eggs. 
  It 
  imparts 
  to 
  persalts 
  of 
  iron 
  a 
  deep 
  red 
  colour. 
  It 
  decomposes 
  carbonates 
  

   with 
  effervescence. 
  

  

  It 
  is 
  bibasic, 
  forming 
  two 
  series 
  of 
  salts, 
  the 
  acid 
  ones 
  are 
  readily 
  crystal- 
  

   lisable 
  ; 
  its 
  salts 
  are 
  very 
  stable, 
  the 
  acid 
  being 
  recoverable 
  from 
  them 
  by 
  decom- 
  

   position 
  with 
  stronger 
  acids. 
  

  

  Acid 
  Ethylomeconate 
  of 
  Baryta. 
  — 
  When 
  carbonate 
  of 
  baryta 
  is 
  added 
  in 
  suc- 
  

   cessive 
  small 
  quantities 
  to 
  water 
  covering 
  solid 
  ethylomeconic 
  acid, 
  lively 
  effer- 
  

   vescence 
  ensues 
  and 
  the 
  acid 
  quickly 
  disappears 
  ; 
  there 
  is 
  formed 
  at 
  the 
  same 
  

   time 
  a 
  small 
  amount 
  of 
  an 
  insoluble 
  yellow 
  salt. 
  If 
  the 
  fluid 
  be 
  filtered 
  imme- 
  

   diately 
  on 
  the 
  cessation 
  of 
  the 
  effervescence, 
  and 
  the 
  vessel 
  be 
  placed 
  under 
  the 
  

   receiver 
  of 
  an 
  air-pump 
  and 
  a 
  vacuum 
  made, 
  a 
  considerable 
  deposit 
  of 
  carbonate 
  

   of 
  lime, 
  which 
  had 
  been 
  held 
  in 
  solution 
  by 
  the 
  carbonic 
  acid 
  now 
  liberated, 
  takes 
  

   place. 
  By 
  a 
  second 
  filtration 
  a 
  clear 
  yellowish 
  fluid 
  is 
  obtained, 
  which 
  yields, 
  on 
  

   evaporation 
  in 
  vacuo 
  or 
  at 
  a 
  gentle 
  heat, 
  very 
  well-defined 
  brilliant 
  rhombic 
  crys- 
  

   tals 
  of 
  a 
  yellow 
  colour. 
  A 
  specimen 
  prepared 
  in 
  this 
  way 
  gave 
  the 
  following 
  

   results 
  : 
  — 
  

  

  {5-053 
  grains, 
  dried 
  at 
  212°, 
  gave 
  

   6-708 
  ... 
  carbonic 
  acid, 
  and 
  

   1-198 
  ... 
  water. 
  

  

  ( 
  5-455 
  grains, 
  dried 
  at 
  212°, 
  gave 
  on 
  ignition 
  with 
  HO 
  S0 
  3 
  , 
  

   \ 
  2-175 
  ... 
  sulphate 
  of 
  baryta. 
  

  

  Calculation. 
  

  

  Carbon, 
  

  

  36-20 
  

  

  36-53 
  

  

  c 
  1B 
  

  

  108 
  

  

  Hydrogen, 
  . 
  

  

  2-63 
  

  

  2-36 
  

  

  H 
  7 
  

  

  7 
  

  

  Oxygen, 
  

  

  . 
  

  

  35-19 
  

  

  <>n 
  

  

  104 
  

  

  Baryta, 
  

  

  26-17 
  

  

  25-92 
  

  

  BaO 
  

  

  76-64 
  

  

  100-00 
  100-00 
  295-64 
  

  

  which 
  lead 
  to 
  the 
  formula, 
  for 
  the 
  dried 
  ethylomeconate 
  of 
  baryta, 
  of 
  

  

  BaO, 
  HO, 
  C 
  4 
  H 
  5 
  C 
  u 
  HO 
  n 
  . 
  

  

  The 
  crystals 
  contain 
  water 
  which 
  they 
  lose 
  on 
  drying, 
  but 
  I 
  missed 
  ascertaining 
  

   the 
  quantity. 
  

  

  Acid 
  Ethylomeconate 
  of 
  Silver. 
  — 
  I 
  obtained 
  this 
  salt 
  by 
  adding 
  an 
  aqueous 
  solu- 
  

   tion 
  of 
  the 
  former 
  to 
  nitrate 
  of 
  silver 
  ; 
  a 
  precipitate 
  was 
  immediately 
  formed, 
  which, 
  

   upon 
  resolution 
  in 
  boiling 
  water, 
  after 
  washing, 
  crystallised 
  out 
  on 
  cooling 
  of 
  the 
  

   fluid 
  in 
  groups 
  of 
  fine 
  small 
  stellate 
  crystals, 
  brilliant 
  and 
  white. 
  This 
  salt 
  is 
  

   remarkably 
  stable, 
  remaining 
  perfectly 
  unchanged 
  in 
  appearance 
  when 
  exposed 
  a 
  

   long 
  time 
  to 
  the 
  diffused 
  daylight 
  of 
  summer 
  ; 
  it 
  gave 
  the 
  following 
  results 
  on 
  

   analysis 
  : 
  — 
  

  

  (5-310 
  grains, 
  dried 
  at 
  212°, 
  gave 
  

   6-215 
  ... 
  carbonic 
  acid, 
  and 
  

   1-053 
  ... 
  water. 
  

  

  