PAINTING  WITH  OXYCHLOMDE  OF  ZINC, 
327 
two  hours  in  winter  and  every  hour  in  summer  ;  which  enables 
us  to  paint  an  apartment  in  one  day  and  inhabit  it  the  same 
day,  without  being  affected  by  the  odor  of  the  paint.  4th.  It 
resists  moisture  and  water,  even  when  boiling,  and  may  be  wash- 
ed with  soap  like  oil  paint.  5th.  In  consequence  of  the  chloride 
of  zinc  which  it  contains,  the  paint  is  eminently  antiseptic  and 
fitted  to  preserve  wood  from  perishing.  6th.  It  possesses  to  a 
very  high  degree  the  quality  of  diminishing  the  combustibility 
of  wood,  fabrics,  and  paper,  and  of  rendering  these  matters  un- 
inflammable. 7th.  It  is  perfectly  innoccuous  both  to  those  who 
prepare  and  those  who  use  it. 
I  have  also  the  honor  of  placing  before  the  Academy  a  new 
translucid  plastic  matter  which  is  formed  with  the  principal  ele- 
ments of  the  paint  of  which  I  have  just  spoken,  but  in  very  dif- 
ferent proportions.  It  is  a  combination  of  potato  fecula  and 
hydrated  chloride  of  zinc,  of  a  sufficient  density  to  swell  the 
fecula  without  dissolving  it.  To  modify  the  hardness  of  the 
matter  and  to  render  it  more  or  less  white  or  more  or  less  opaque, 
certain  salts  or  powdered  matters  are  added,  such  as  oxide 
of  zinc,  sulphate  of  baryta,  &c.  This  plastic  matter  is  prepared 
cold  by  moistening  the  fecula  and  other  matters  with  chloride  of 
zinc.  This  new  compound  is  easily  moulded,  and  solidifies  in 
the  mould  like  plaster.  The  objects  thus  obtained  are  as  trans- 
lucid  as  horn,  bone,  or  ivory ;  but  to  obtain  this  translucidness 
very  little  or  none  of  the  moist  pulverulent  substances  must  be 
introduced,  except  sulphate  of  baryta.  This  salt,  although  in- 
soluble, give  very  little  opacity  to  the  matter.  This  is  not  the 
case  with  oxide  of  zinc  or  carbonate  of  lime. 
To  keep  the  objects  thus  obtained  from  moisture,  they  are 
covered  with  one  or  two  layers  of  good  varnish. 
Any  color  may  be  given  to  this  new  matter,  and  it  may  be 
obtained  more  or  less  hard ;  it  may  even  be  obtained  as  supple 
as  caoutchouc,  but  not  elastic. 
This  new  plastic  compound  may  be  used  for  moulding  many 
objects  of  art  and  ornament,  and  in  the  manufacture  of  many 
things  requiring  either  hardness,  suppleness,  or  transparency. 
This  substance  may  replace,  in  many  cases,  plaster,  marble, 
ivory,  horn,  bone,  gutta-percha,  gelatine,  etc. — London  Chem., 
May  1858,  from  Oomptes  Bendus,  March  1858. 
