Chemical  Notes, 
(  Am.  Jour.  Pharm. 
1      June,  1879. 
Arnaudon  (same  journal,  p.  524)  has  also  found  in  the  quebracho- 
bark  a  coloring  matter  which  colors  fabrics  a  beautiful  yellow.  The 
aqueous  decoction  of  the  wood  is  slightly  acid,  of  reddish  yellow  color 
when  concentrated,  becomes  turbid  on  cooling,  and  deposits  a  reddish- 
brown  substance.  On  boiling  with  dilute  sulphuric  acid  no  gallic  acid 
is  separated  from  the  quebracho-tannic  acid. 
At  the  late  Leather  Exhibition  in  Berlin,  quebracho  tanned  leather 
of  different  qualities  was  shown.  Quebracho  is  said,  under  circum- 
stances', to  be  quite  as  well  adapted  as  sumac  for  the  manufacture  of 
morocco  leathers,  especially  for  such  as  are  to  be  of  a  dark  color.. 
— Dingier 's  ^Journal,  231,  p.  451. 
'  M.  Fileti  has  obtained,  by  the  action  of  bromine  upon  cinchonia,  in- 
sealed  tubes,  a  number  of  products,  the  chief  one  of  which  seems  to 
be  perbromanthracene,  CuBr10.  The  analytical  figures  at  least  corres- 
pond very  closely  to  this  formula.  Perbromanthracene  has  not  as  yet 
been  obtained  direct  from  anthracene,  the  highest  brominated  com- 
pound so  obtained  being  C14BrgH2.  Fileti  thinks  that  the  anthracene 
group  of  atoms  may  constitute  the  nucleus  of  the  cinchonia  molecule 
and  possibly  also  of  quinia  and  other  alkaloids.  He  promises  to  con- 
tinue the  study  of  this  most  interesting  derivative,  and  to  extend  the 
same  experiments  to  the  alkaloids  associated  with  cinchonia.— Ber.  d.. 
Chem.  Ges.,  xii,  p.  423. 
Analytical  Chemistry. — F.  Beilstein  and  L.  Jarvein  have  described 
a  method  for  the  accurate  determination  of  zinc  in  the  electrolytic  way*. 
The  nitrate  or  sulphate  solution  is  treated  with  sodium  hydrate  until  a 
precipitate  remains,  and  then  with  potassium  cyanide  until  a  clear  solu- 
tion results.  The  platinum  electrodes  are  now  dipped  into  the  fluid^, 
and  the  current  from  four  Bunsen  cells  is  passed  through  it.  If  the 
amount  of  liquid  is  small,  it  becomes  quite  warm,  in  which  case  the 
beaker-glass  can  be  cooled  by  placing  it  in  a  dish  of  water.  On  an 
average,  about  "i  gram  of  zinc  will  be  precipitated  per  hour  under  these 
circumstances.  When  all  the  zinc  is  supposed  to  be  precipitated,  the 
electrodes  are  lifted  out,  which  can  be  done  without  any  danger  of  loss,, 
the  zinc  is  washed  with  water,  then  with  alcohol  and  finally  with  ether, 
and  dried  in  a  dessicator. 
The  zinc  obtained  in  this  way  can  be  heated  for  hours  in  an  air-bath 
at  ioo°  without  oxydizing  in  the  slightest  degree. 
After  weighing,  the  zinc  is  dissolved  off  the  electrode  with  hydro- 
