English  Lithographic  Ink,  Pulverize
and  mix  together  12  parts  of  shellac,  8
of  mastic,  and  melt  in  1  of  Venetian
turpentine.  Remove  the  vessel  from
the  fire,  add  16  parts  of  wax  and  6  of
tallow,  and  when  they  are  melted  add
6  parta  of  hard  tallow  soap  cut  into
shavings,  and  11  parts  of  lampblack.
The  mass,  after  having  been  inti-
mately mixed  by  boiling^  la  allowed  to
cool  off  somewhat,  and  is  then,  while
still  in  a  liquid  state,  poured  upon  a
marble  slab,  and,  when  cold,  cut  into
square  pieces.
The  principal  property  of  a  good
lithographic  ink  is  that  it  does  not
penetrate  into  the  stone,  so  that  the  most
delicate  lines  of  a  drawing  will  stand  a
great  number  of  impressions.  It  must
therefore  be  capable  of  resisting  the
acid,  with  which  the  stone  is  prepared,
to  such  a  degree  that  not  even  the
smallest  particle  of  the  fatty  substances
is  attacked  by  it.
Writing-ink.  Although  there  is  per-
haps no  other  chemical  preparation  in
such  general  use  as  writing-ink,  but  few
inks  answer  all  requirements.  This
may  be  explained  by  the  circumstance
that  receipts  for  ink  cannot  be  calcu-
lated according  to  a  chemical  formula,
but  largely  depend  on  experiments,  and
that  we  are  forced  to  use  the  collected
results  of  such  experiments.  A  good
black  writing-ink  must  readily  flow
from  the  pen,  show  either  at  once  or  in
a  short  time  a  deep  black  color,  and
must  not  attack  the  pen  or  the  paper.
When  kept  in  a  hermetically  closed
vessel  no  sediment  of  any  account
should  be  formed,  although  such  will !


always  be  fonnd  in  ordinary  inkstands,
and  this  the  quicker  the  more  the  ink
comes  in  contact  with  atmospheric  air.
