128  A  MALLEABLE  AMALGAM  FOR  DENTISTS. 
KINIC  ACID  IN  THE  LEAVES  OF  THE  VACCINIUM  MYRTILLUS. 
Zwenger  says  he  has  found  quinic  acid  in  the  leaves  of  the 
Vaecinium  Myrtillus.  His  process  for  extracting  it  is  the  fol- 
lowing :  He  boils  the  leaves  (collected  in  May)  with  milk  of  lime, 
and  precipitates  the  clear  solution  with  alcohol.  The  precipitate 
he  dissolves  in  water,  adds  a  little  acetic  acid,  and  the  neutral 
acetate  of  lead  to  throw  down  the  coloring  and  other  foreign 
matters.  After  having  removed  the  lead  by  sulphuretted  hydro- 
gen he  evaporates  the  liquor  to  a  syrupy  consistence,  and  then 
sets  it  aside  for  some  days,  when  quinate  of  lime  is  deposited. 
This  he  dissolves  in  water,  adds  sulphuric  acid  to  take  away  the 
lime,  and  evaporates  in  a  water  bath.  The  syrupy  residue  he 
dissolves  in  alcohol,  and  in  this  solution  there  forms  sometimes 
oblique  prismatic  crystals  which  possess  all  the  characters  of 
quinic  acid — Ann.  der  Qhem.  und  Pharm.  from  Chem.  Neivs, 
London^  Oct.  6,  1860. 
A  MALLEABLE  AMALGAM  FOR  DENTISTS. 
As  to  the  brittleness  which  cadmium  is  said  to  communicate 
when  combined  with  any  other  metal,  the  facts  are,  some  of  its 
alloys,  even  with  malleable  metals,  are  "  brittle."  But  others 
are  highly  tenacious  and  malleable.  Its  alloys  with  gold,  plati- 
num and  copper  afford  instances  of  the  former.  Its  combina- 
tions with  lead,  tin,  and  to  a  certain  extent  with  silver  and  mer- 
cury, are  examples  of  the  latter.  An  alloy  of  two  parts  silver 
and  one  of  cadmium  is  perfectly  malleable  and  very  hard  and 
strong  ;  with  equal  parts  of  each  it  is  also  malleable,  but  pos- 
sesses less  tenacity ;  but  when  mixed  in  the  proportions  of  two 
parts  of  cadmium  and  one  part  of  silver  it  is  brittle.  Equal 
parts  of  cadmium  and  mercury  form  a  tough  and  highly  malle- 
able composition ;  in  the  proportion  of  two  parts  of  the  latter 
to  one  of  the  former,  the  amalgam  is  nearly  equal  in  malleabil- 
ity, but  possesses  less  strength.  These  mixtures  are  remarkable 
in  view  of  the  fact  that  most  amalgams  are  exceedingly  frail  and 
brittle.  A  mixture  of  two  or  three  parts  of  tin  with  one  part 
of  mercury  is  so  fragile  as  almost  to  drop  to  pieces  in  handling ; 
the  amalgams  with  lead,  bismuth,  &c.  are  similar. — Chem,  News, 
London,  Sept,  29,  1860. 
