A  NEW  PHOTOGRAPHIC  VARNISH,  ETC. 
449 
given  to  the  picture  by  this  varnish  is  by  no  means  of  a  delicate 
character,  and  requires  glazing  before  it  is  at  all  presentable ; 
and  the  yellowish  tint  which  it  leaves  on  drying  frequently  gives 
photographs  the  appearance  of  having  been  insufficiently  washed. 
For  these  reasons  I  have  adopted  the  use  of  a  spirit  varnish, 
which  I  find  remarkably  suitable.  Its  cost  is  very  moderate,  it 
does  not  turn  yellow,  and  it  is  easy  of  application,— the  latter 
qualification  being  very  desirable  when  large  numbers  of  cartes 
de  visite  pictures  are  to  be  coated.  The  beauty  of  the  picture  is 
greatly  enhanced  by  the  use  of  this  varnish,  as  it  does  not  be- 
stow too  much  lustre,  and,  being  applied  in  very  minute  quanti- 
ties, there  is  no  fear  of  its  becoming  brittle  and  liable  to  peel  off 
when  dry. 
The  method  of  preparing  is  as  follows  : — Five  parts  of  finely 
powdered  gum  sandrach  are  put  into  a  vessel  with  twenty  parts 
of  absolute  alcohol,  and  when  the  gum  has  been  entirely  dissolved 
by  shaking,  two  parts  of  Venetian  turpentine  are  added  ;  the 
mixture  is  again  agitated,  and  then  one  and  a  half  parts  of  oil 
of  lavender  or  oil  of  turpentine,  and  finally  one  and  a  half  parts 
of  camphor,  powdered  as  fine  as  possible,  are  added,  and  the 
whole  shaken  up  till  completely  dissolved,  the  entire  operation 
being  performed  in  about  ten  minutes.  The  varnish  should  be 
filtered  or  allowed  to  stand  for  a  few  days,  and  then  poured  off; 
if  it  does  not  give  sufficient  lustre,  a  further  quantity  (from  half 
to  one  part)  of  gum  sandrach  is  added. 
The  varnish  is  applied  to  pictures  by  means  of  a  broad  goat's- 
hair  brush,  an  inch  or  inch  and  a  half  in  breadth ;  it  can  be  laid 
on  very  rapidly,  and  when  coating  small  pictures  it  is  a  matter 
of  no  importance  if  the  narrow  margin  of  cards  is  covered  with 
it.  A  few  minutes  is  sufficient  to  dry  the  varnish,  which  then 
forms  an  admirable  protection  to  the  picture,  especially  in  any 
of  its  defective  parts,  where  it  may  have  been  improved  and 
touched  up  with  a  brush.  It  sometimes  happens,  when  the  al- 
bumenized  paper  has  received  but  an  exceedingly  slight  coating 
of  albumen,  that  small  spots  are  formed  on  the  application  of  the 
varnish,  but  these  are  not  visible  on  a  dark  ground  ;  should, 
however,  such  imperfections  occur  on  vignetted  pictures,  the  only 
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