272 
PATENT  GUM. 
be  employed  with  advantage  to  produce  a  Turkey  red  on  cotton, 
and  one  which  could  not,  was,  that  the  first  contained  a  large 
portion  of  free  fatty  acids,  whilst  the  latter  was  nearly  neutral. 
This  led  M.  Pelouze  first  to  prepare,  artificially,  oils  of  good 
quality  for  Turkey  red  by  mixing  oleic  acid  with  neutral  oils  ; 
and,  secondly,  to  the  interesting  scientific  observation  that  oils 
were  susceptible  of  undergoing  a  spontaneous  fermentation  as 
well  as  saccharine  juices,  or  other  organic  fluids.  Thus,  immedi- 
ately the  neutral  fatty  matters  in  the  cells  of  fruits  or  roots  are 
brought  into  contact  with  the  ferment  which  all  vegetable  sub- 
stances contain,  by  breaking  the  cells  in  which  the  fatty  mat- 
ters are  deposited,  the  oil  enters  into  fermentation,  and  the  fatty 
acids  are  liberated  from  the  glycerine  with  which  they  had  been 
combined.  This  discovery  gives  us  an  insight  into  the  acidity 
of  some  oils  and  the  rancidness  of  others. — London  Chemist, 
March,  1858. 
PATENT  GUM. 
By  Prof.  Calvert. 
One  of  my  late  assistants,  Mr.  Edward  Hunt,  has  just  patented 
a  discovery  of  much  value  to  several  trades,  and  especially  to 
calico  printers,  who  employ  large  quantities  of  various  prepara- 
tions of  farina,  sago,  wheat,  starch,  and  flour,  as  a  substitute  for 
gum  arabic,  to  thicken  the  mordants  and  steam  colors,  We  shall 
better  appreciate  the  value  of  the  discovery  made  by  Mr.  Hunt, 
when  we  reflect  that  hundreds  of  tons  of  the  above  preparations 
are  employed  annually,  and  that  most  of  the  substances  used  are 
articles  of  food,  for  by  this  discovery  a  great  saving  in  quantity 
is  effected,  two  pounds  of  Mr.  Hunt's  gum  thickening  as  well  as 
three  pounds  of  ordinary  calcined  farina.  This  new  gum  pre- 
sents also  the  three  following  advantages,  viz.,  being  nearly 
white,  perfectly  soluble  in  cold  water,  and  this  solution  not  be- 
ing acid.  The  patent  gum  is  manufactured  by  adding  to  one 
ton  of  dry  farina  60  gallons  of  buttermilk,  and  calcining  the 
whole  in  the  ordinary  way.  Strange  to  say,  the  action  of  the 
lactic  acid  on  the  caseine  and  albumen  of  the  buttermilk,  is  such 
as  to  render  them,  as  well  as  the  farina,  soluble  in  water. — Lon- 
don Chemist,  March,  1858. 
