﻿Carey: 
  A 
  starch 
  gel 
  

  

  459 
  

  

  TABLE 
  II 
  

   General 
  averages 
  from 
  Tables 
  III-XI 
  (see 
  Appendix) 
  

  

  Adsorption 
  water 
  per 
  gram 
  Adsorption 
  water 
  per 
  

   Temperature 
  dry 
  starch 
  gel 
  on 
  basis 
  gram, 
  corrected 
  accord- 
  

  

  degrees 
  Centigrade 
  of 
  original 
  weight 
  ing 
  to 
  Table 
  I 
  

  

  correction 
  negligible 
  

  

  8.5-10.5 
  

  

  0.864 
  

  

  17.5 
  

  

  0.896 
  

  

  24 
  

  

  0.916 
  

  

  35 
  

  

  1. 
  140 
  

  

  50 
  

  

  2.426 
  

  

  60 
  

  

  2,807 
  

  

  70 
  

  

  3-153 
  

  

  80 
  

  

  A 
  

  

  3427 
  

  

  90 
  

  

  3-713 
  

  

  1 
  1 
  

  

  il 
  

  

  «< 
  

  

  tt 
  

  

  1. 
  143 
  

   2.448 
  

  

  2.865 
  

  

  3i274 
  

  

  3.768 
  

  

  4.411 
  

  

  In 
  MacDougal's 
  work 
  with 
  artificial 
  biocolloid 
  mixtures 
  (i), 
  

   mainly 
  of 
  agar 
  but 
  containing 
  some 
  protein, 
  an 
  increase 
  in 
  the 
  

   total 
  amount 
  of 
  swelling 
  was 
  found 
  to 
  a 
  maximum 
  point 
  between 
  

   39° 
  and 
  46° 
  C. 
  MacDougal 
  (2) 
  has 
  also 
  shown 
  a 
  greater 
  swelling 
  

   of 
  agar 
  than 
  of 
  gelatine 
  in 
  distilled 
  water 
  at 
  the 
  same 
  temperature, 
  

   and 
  in 
  mixtures 
  of 
  the 
  two 
  the 
  swelling 
  increased 
  as 
  the 
  percentage 
  

   of 
  agar 
  in 
  the 
  mixture 
  was 
  increased. 
  From 
  these 
  results, 
  and 
  also 
  

   from 
  those 
  shown 
  in 
  this 
  paper, 
  it 
  would 
  appear 
  that 
  at 
  least 
  

   carbohydrate 
  gels 
  behave 
  somewhat 
  similarly. 
  

  

  This 
  increased 
  adsorption 
  with 
  rise 
  in 
  temperature 
  does 
  not 
  

   agree 
  with 
  Taylor 
  (7, 
  p. 
  155), 
  who 
  states 
  that, 
  according 
  to 
  

   LaChatelier's 
  theorem, 
  heat 
  diminishes 
  and 
  cold 
  and 
  pressure 
  in- 
  

   crease 
  imbibition. 
  But 
  Meyer 
  (5) 
  refers 
  to 
  the 
  fact 
  that 
  gels 
  

   dried 
  in 
  the 
  air 
  will 
  swell 
  again 
  if 
  put 
  into 
  water, 
  the 
  swelling 
  

   being 
  greater 
  the 
  higher 
  the 
  temperature 
  of 
  the 
  water. 
  The 
  tem- 
  

   peratures 
  at 
  which 
  the 
  writer's 
  experiments 
  were 
  performed 
  varied 
  

   slightly 
  from 
  that 
  taken 
  as 
  the 
  average, 
  but 
  in 
  no 
  case 
  was 
  it 
  

   enough 
  to 
  be 
  noticeable 
  in 
  the 
  amounts 
  of 
  water 
  adsorbed. 
  

  

  The 
  preparation 
  of 
  this 
  starch 
  gel 
  was 
  undertaken 
  with 
  the 
  

   idea 
  of 
  obtaining 
  a 
  pure 
  carbohydrate 
  gel, 
  which 
  on 
  account 
  of 
  its 
  

   hydratlve 
  capacity 
  would 
  be 
  suitable 
  for 
  experimentation 
  under 
  

   various 
  conditions. 
  In 
  a 
  sense 
  it 
  might 
  be 
  said 
  to 
  simulate 
  a 
  

   cellulose 
  membrane, 
  but 
  it 
  would 
  be 
  unsafe 
  to 
  carry 
  the 
  comparison 
  

   too 
  far. 
  Inasmuch 
  as 
  the 
  hydration 
  of 
  organic 
  elastic 
  gels 
  is 
  of 
  

   fundamental 
  importance 
  in 
  many 
  physiological 
  problems 
  which 
  

   are 
  attracting 
  great 
  attention 
  today, 
  it 
  has 
  seemed 
  worth 
  while 
  

   to 
  place 
  on 
  record 
  the 
  results 
  of 
  the 
  above 
  experiments 
  as 
  a 
  con- 
  

   tribution 
  to 
  a 
  partial 
  knowledge 
  of 
  some 
  of 
  the 
  properties 
  which 
  

  

  