GLEANINGS  FROM  FRENCH  JOURNALS. 
331 
So  far,  botanists  have  found  but  two  vegetables  which  furnish 
camphor  in  quantity  sufficient  for  its  extraction, — the  Oamphora 
officinarum,  and  the  Dryabalanops  camphor  a,  which  grows  in 
Sumatra. 
The  Chinese  gather  it  on  another  plant,  where  it  collects  under 
the  form  of  little  clots  at  the  bases  of  the  leaves  and  at  the  bot- 
tom of  the  corolla. 
The  odor  of  this  camphor  differs  but  little  from  that  of  ordi- 
nary camphor,  nevertheless  it  possesses  some  peculiarity  when 
rubbed  between  the  fingers. 
This  camphor  is  so  scarce  that  its  price  equals  nearly  that  of 
gold.  The  Emperor  and  the  mandarins  only  enjoy  the  luxury 
of  its  use  on  their  persons.  If  it  could  be  imitated  it  would  be 
a  source  of  wealth. 
Manufacture  of  tartaric  acid  from  the  marc  of  grapes.  —The 
only  source  heretofore  utilized  for  obtaining  tartaric  acid  is  the 
le'es  of  wine  casks.  Messrs.  Inette  &  Ponteves  propose  to  em- 
ploy the  marc  of  the  grape,  and  by  the  following  process  to  re- 
move the  acid  from  the  tartrate  of  lime  it  contains  : 
The  pressed  marc  is  submitted  to  an  ebullition  of  some  hours 
with  about  two  per  cent,  of  sulphuric  acid,  with  the  intention  of 
liberating  the  tartaric  acid  ;  a  portion  of  cellulose  is  transformed 
into  glucose,  and  as  the  marc  contains  nearly  always  some  sugar 
which  has  escaped  fermentation,  the  liquid  may  be  fermented, 
and  alcohol  obtained  from  it  by  distillation.  The  residue  is 
saturated  with  lime,  which  produces  the  tartrate  of  lime,  from 
which  the  tartaric  acid  is  separated  by  known  processes.  The 
quantity  of  marc  yielded  by  a  million  hectolitres  of  wine  can? 
according  to  the  authors,  produce  200,000  kilogrammes  (437,000 
lbs.)  of  tartaric  acid  ;  the  marcs  of  the  south  of  Europe  contain 
3  to  4  per  cent,  of  tartrate  of  lime. 
It  sometimes  happens  that  the  presence  of  magnesia  or  pec- 
tinous  matters  interfere  with  the  decomposition  of  tartrate  of 
lime  by  the  sulphuric  acid.  It  is  then  preferable  to  treat  the 
marc  with  an  alkaline  carbonate,  in  the  manner  to  produce  car- 
bonate of  lime  and  an  alkaline  tartrate.  To  effect  this  double 
decomposition  the  marc  is  suspended  in  four  or  five  times  its 
weight  of  water,  and  a  quantity  of  carbonate  of  soda  added,  so  that 
