478 
VARIETIES. 
Tooth  Paste. — The  best  plastic  tooth  paste  is  made  in  the  following  way: 
1.  1  part  finely  powdered  glass  is  mixed  with  3  parts  finely  divided  oxide 
of  zinc  entirely  free  of  carbonate.  2.  50  parts  of  solution  of  chloride  of 
zinc,  spec.  grav.  1-5  to  1-6,  is  mixed  with  1  part  of  borax  dissolved  in  the 
smallest  possible  quantity  of  hot  water  ;  all  parts  are  taken  by  weight. 
If  it  is  to  be  used  for  filling  teeth,  the  powder  No.  1  is  mixed  with  a 
sufficient  quantity  of  the  solution  No.  2  to  make  an  even  paste ;  during  the 
operation  the  mass  generates  a  moderate  heat. 
The  addition  of  powdered  glass  is  necessary  to  impart  to  the  mass  the 
requisite  firmness.  On  adding  the  solution  of  borax  to  the  solution  of 
chloride  of  zinc,  a  precipitate  of  borate  of  zinc  is  at  first  produced,  which, 
however,  easily  dissolves  in  the  excess  of  the  zinc  solution.  Borax  actsby 
delaying  the  hardening  and  subsequently  to  increase  the  hardness  of  the 
mass  j  without  addition,  the  paste  hardens  so  quickly  as  to  leave  scarcely 
time  to  mould  it  into  the  required  shape. 
This  paste  is  of  a  dazzling  white,  which  is  never  met  with  in  teeth,  and 
it  may  be  therefore  advisable  to  mix  No.  1,  previous  to  adding  the  liquid, 
with  a  small  quantity  of  ochre.  In  one  day  the  mass  has  become  so  hard 
as  to  require  considerable  force  to  break  it  up  ;  its  ultimate  hardness  is 
that  of  marble ;  it  is  not  affected  by  water,  and  may  perhaps  be  found  use- 
ful for  other  purposes  where  a  plastic  mass  is  required — Pharmac.  Zeitung. 
— Schweiz.  Zeitschr.f.  Pharm.  1859,  16.  j.  m.  m, 
Parisian  Wash  Powder. — The  ladies'  toilet  table  has  been  enriched  by  the 
"Parisian  Wash  Powder,"  which  is  prepared  in  the  following  manner: 
Kice  is  softened  in  pure  water,  which  is  daily  replaced  by  fresh  water  until 
the  rice  can  be  easily  mashed  ;  all  the  water  is  then  drawn  off,  the  rice 
crushed,  the  pasty  mass  mixed  with  water  to  a  milky  liquid,  and  this 
brought  on  a  sieve  or  a  cloth  which  must  not  be  too  thick.  After  settling, 
the  fine  powder  is  collected,  dried,  and  a  small  quantity  of  soda  added. — 
Schweiz.  Zeitschr.f.  Pharm.  1859,  49. 
Mr.  Fox  Talbot's  New  Discovery, — Photoglyphic  Engraving. — The  subject 
of  engraving  steel  or  copper  plates  by  means  of  photography,  is  one  which 
has  deservedly  attracted  the  attention  of  the  leading  men  of  science,  both 
in  this  country  and  on  the  Continent.  .  ;  .  .  We  have  been  favored  with 
the  inspection  of  some  new  photographic — or,  to  speak  more  correctly 
