﻿Skey. 
  — 
  Osomose, 
  as 
  the 
  Cause 
  of 
  Susjjension 
  of 
  Clay 
  in 
  Water. 
  489 
  

  

  There 
  is, 
  perliaps, 
  one 
  point 
  in 
  respect 
  to 
  this, 
  about 
  which 
  you 
  may 
  

   require 
  further 
  information 
  ere 
  you 
  would 
  be 
  prepared 
  to 
  give 
  an 
  opinion 
  

   respecting 
  the 
  accuracy 
  of 
  my 
  theory. 
  It 
  may 
  be 
  asked 
  whether, 
  in 
  all 
  

   instances 
  of 
  persistent 
  clay 
  diffusion, 
  there 
  is 
  sufficient 
  soluble 
  saline 
  matter 
  

   present 
  of 
  such 
  a 
  nature, 
  and 
  which 
  is, 
  besides, 
  so 
  unevenly 
  distributed, 
  as 
  

   to 
  enable 
  dialysis 
  to 
  be 
  carried 
  on 
  to 
  the 
  necessary 
  extent 
  ? 
  

  

  In 
  regard 
  to 
  this, 
  I 
  would 
  reiterate 
  the 
  statement 
  which 
  I 
  have 
  made, 
  

   that 
  dialysis 
  is 
  best 
  produced 
  by 
  very 
  weak 
  saline 
  solution, 
  and 
  I. 
  would, 
  

   besides, 
  remind 
  you 
  thfit 
  by 
  far 
  the 
  most 
  effective 
  solutions 
  for 
  this 
  purpose 
  

   are 
  those 
  of 
  the 
  alkalies, 
  and 
  it 
  is 
  precisely 
  matter 
  of 
  this 
  kind, 
  which, 
  as 
  it 
  

   happens, 
  is 
  certain 
  to 
  be 
  present 
  and 
  unequally 
  distributed 
  in 
  any 
  clay 
  

   water 
  we 
  may 
  ever 
  prepare. 
  

  

  In 
  all 
  clay, 
  as 
  you 
  are 
  aware, 
  some 
  alkaline 
  matter 
  is 
  present, 
  and 
  in 
  

   such 
  a 
  form 
  that 
  it 
  gradually 
  passes 
  into 
  solution. 
  Again, 
  ammonia 
  

   can, 
  as 
  we 
  know, 
  scarcely 
  be 
  excluded 
  from 
  the 
  water 
  through 
  which 
  clay 
  

   may 
  be 
  diffused, 
  and 
  it 
  signifies 
  not 
  where 
  the 
  alkalies 
  are, 
  whether 
  with 
  

   the 
  clay 
  or 
  the 
  water, 
  so 
  long 
  as 
  they 
  are 
  not 
  equally 
  diffused 
  throughout 
  

   both. 
  

  

  In 
  this 
  connection 
  it 
  is 
  proper 
  to 
  note 
  the 
  fact 
  which 
  has 
  been 
  recently 
  

   discovered* 
  : 
  — 
  " 
  That 
  the 
  power 
  which 
  water 
  possesses 
  of 
  sustaining 
  clay 
  in 
  

   suspension 
  is 
  increased 
  by 
  the 
  addition 
  of 
  small 
  quantities 
  of 
  the 
  alkalies 
  or 
  

   their 
  carbonates," 
  and 
  that 
  water, 
  whose 
  power 
  of 
  sustaining 
  clay 
  had 
  been 
  

   destroyed 
  by_an 
  acid, 
  had 
  this 
  power 
  restored 
  in 
  great 
  measure 
  by 
  any 
  of 
  

   the 
  alkalies. 
  Now 
  precisely 
  the 
  same 
  kind 
  of 
  thing 
  would 
  happen 
  in 
  the 
  

   case 
  of 
  albumen, 
  and 
  conversely 
  salts 
  in 
  large 
  quantity 
  retard 
  or 
  prevent 
  

   the 
  alkalies 
  acting 
  in 
  this 
  manner. 
  The 
  analogy 
  therefore 
  between 
  clay 
  and 
  

   albumen 
  in 
  respect 
  to 
  my 
  subject, 
  is 
  obviously 
  of 
  so 
  wide 
  and 
  general 
  a 
  

   character 
  that 
  we 
  may 
  safely 
  assume 
  them 
  to 
  be 
  alike 
  capable 
  of 
  assisting 
  

   in 
  osomotic 
  action 
  and 
  its 
  results. 
  

  

  In 
  conclusion, 
  I 
  would 
  state 
  that 
  I 
  have 
  thus 
  singled 
  out 
  the 
  persistent 
  

   suspension 
  of 
  clay 
  for 
  explanation 
  in 
  place 
  of 
  the 
  persistent 
  suspension 
  of 
  

   substances 
  of 
  a 
  like 
  nature 
  generally, 
  because 
  the 
  question 
  of 
  clay 
  suspen= 
  

   sion 
  is 
  to 
  me 
  of 
  particular 
  interest 
  as 
  being 
  one 
  I 
  have 
  had 
  in 
  my 
  mind 
  for 
  

   a 
  long 
  time 
  past, 
  and 
  I 
  obtained 
  by 
  experiment 
  results 
  thereon 
  which 
  I 
  am 
  

   persuaded 
  are 
  of 
  some 
  value 
  in 
  regard 
  to 
  its 
  settlement. 
  

  

  Granted, 
  however, 
  that 
  this 
  attempt 
  of 
  mine 
  at 
  the 
  explanation 
  of 
  the 
  

   persistent 
  suspension 
  of 
  clay 
  is 
  a 
  successful 
  one, 
  the 
  principle 
  thus 
  involved 
  

   is 
  so 
  easy 
  to 
  make 
  a 
  general 
  application 
  of, 
  to 
  the 
  explanation 
  of 
  those 
  

  

  * 
  Suspension 
  of 
  Clay 
  in 
  Water, 
  by 
  William 
  Durham, 
  F.E.S.E. 
  Kead 
  before 
  the 
  

   Physical 
  Society 
  of 
  Edinburgh, 
  28th 
  January, 
  1874* 
  

  

  a32 
  

  

  