﻿392 
  OF 
  AN 
  IMPROVED 
  

  

  of 
  five 
  parts 
  of 
  air 
  and 
  three 
  of 
  hydrogen 
  ; 
  also 
  with 
  a 
  reservoir 
  of 
  

   hydrogen.* 
  

  

  These 
  arrangements 
  being 
  made, 
  exhaust 
  the 
  bottles; 
  and 
  admitting 
  

   two 
  or 
  three 
  volumes 
  of 
  hydrogen, 
  exhaust 
  again. 
  By 
  repeating 
  this 
  

   part 
  of 
  the 
  process, 
  nothing 
  but 
  hydrogen 
  will 
  remain 
  in 
  the 
  vessel. 
  

   Let 
  the 
  zero 
  of 
  the 
  descending 
  scale 
  be 
  situated 
  on 
  a 
  level 
  with 
  the 
  

   surface 
  of 
  the 
  mercury 
  in 
  the 
  gage 
  tube, 
  and 
  then 
  admit 
  eight 
  volumes 
  

   of 
  the 
  mixture, 
  which 
  will 
  be 
  known 
  to 
  have 
  entered 
  when 
  the 
  sur- 
  

   face 
  of 
  the 
  mercurial 
  column 
  has 
  fallen 
  to 
  eight 
  on 
  that 
  scale. 
  All 
  

   the 
  cocks 
  being 
  closed, 
  ignite 
  the 
  platina 
  wire. 
  The 
  explosion 
  will 
  be 
  

   known 
  to 
  take 
  place, 
  both 
  by 
  the 
  flash 
  and 
  sharp 
  noise 
  which 
  it 
  pro- 
  

   duces. 
  As 
  soon 
  as 
  these 
  indications 
  are 
  perceived, 
  the 
  cock 
  commu- 
  

   nicating 
  with 
  the 
  gage 
  may 
  be 
  re-opened. 
  Nearly 
  three 
  volumes 
  of 
  

   the 
  mixture 
  will 
  be 
  found 
  to 
  have 
  disappeared, 
  and 
  by 
  the 
  time 
  that 
  

   the 
  thermometer 
  indicates 
  the 
  temperature 
  to 
  be 
  in 
  statu 
  quo, 
  it 
  will 
  

   be 
  found 
  that 
  the 
  deficit 
  arising 
  from 
  the 
  combustion 
  will 
  a 
  little 
  ex- 
  

   ceed 
  that 
  quantity. 
  

  

  In 
  analysing 
  gaseous 
  compounds 
  of 
  carbon 
  with 
  hydrogen, 
  this 
  ap- 
  

   paratus 
  may 
  be 
  advantageously 
  employed 
  ; 
  due 
  proportions 
  of 
  the 
  car- 
  

   buret 
  and 
  of 
  oxygen 
  gas 
  being 
  previously 
  mingled 
  in 
  an 
  appropriate 
  

   vessel 
  over 
  water. 
  Suppose, 
  for 
  instance, 
  defiant 
  gas 
  were 
  in 
  ques- 
  

   tion 
  ; 
  one 
  volume 
  of 
  it 
  being 
  mixed 
  with 
  four 
  of 
  oxygen 
  : 
  after 
  the 
  ex- 
  

   plosion, 
  two 
  volumes 
  will 
  be 
  found 
  wanting 
  ; 
  because, 
  in 
  one 
  volume 
  

   of 
  the 
  carburet, 
  there 
  are 
  two 
  of 
  hydrogen 
  and 
  two 
  of 
  carbon 
  vapour. 
  

   Each 
  volume 
  of 
  the 
  latter, 
  will 
  unite 
  with 
  one 
  of 
  oxygen, 
  without 
  al- 
  

   tering 
  its 
  volume. 
  The 
  two 
  volumes 
  of 
  hydrogen 
  will 
  take 
  one 
  of 
  

   oxygen, 
  and 
  be 
  condensed 
  with 
  it 
  into 
  water. 
  Of 
  course, 
  in 
  lieu 
  of 
  

   the 
  five 
  volumes 
  introduced, 
  two 
  volumes 
  of 
  carbonic 
  acid, 
  and 
  one 
  

   residual 
  volume 
  of 
  oxygen 
  will 
  remain. 
  

  

  By 
  means 
  of 
  the 
  forcing 
  air 
  pump, 
  described 
  in 
  the 
  preceding 
  

   pages, 
  the 
  gas 
  may 
  be 
  transferred 
  to 
  a 
  receiver, 
  and 
  washed 
  with 
  am- 
  

   monia, 
  or 
  milk 
  of 
  lime, 
  and 
  then 
  allowed 
  again 
  to 
  enter 
  the 
  iron 
  bottle. 
  

  

  * 
  The 
  necessary 
  mixtures 
  are 
  effected 
  either 
  by 
  means 
  of 
  the 
  volumeters 
  or 
  the 
  sliding 
  rod 
  

   gas 
  measure, 
  of 
  which 
  I 
  published 
  engravings 
  and 
  descriptions 
  in 
  Silliman's 
  American 
  Jour- 
  

   nal 
  of 
  Science, 
  vol. 
  12, 
  page 
  36, 
  1827 
  ; 
  and 
  in 
  the 
  London 
  Philosophical 
  Magazine 
  for 
  1828, 
  

   vol. 
  32, 
  page 
  126. 
  

  

  