i 
344  PREPARATION  OF  PLATINUM-BLACK. 
intensely  bitter  than  that  of  any  other  body  with  which  the 
author  is  acquainted.  When  heated,  it  melts  and  evolves  fumes 
which,  when  inhaled,  possess  a  bitter  and  acrid  taste  ;  when  the 
heat  is  continued,  it  becomes  carbonized  and  burnt  away,  with- 
out leaving  any  trace  of  ash. 
It  dissolves  in  water  more  easily  than  in  alcohol,  and  its 
solutions  are  perfectly  neutral.  It  does  not  exert  the  least 
reaction  upon  ferridcyanide  of  potassium,  sulphate  of  copper, 
nitrate  of  silver,  chloride  of  platinum,  tincture  of  iodine, 
protosulphate  of  iron,  perchloride  of  iron,  and  chromate  of 
potash.  Nitric  and  muriatic  acids  give  it  a  yellow  color,  whilst 
by  the  addition  of  concentrated  sulphuric  acid  a  beautiful  red- 
dish-violet color  is  produced,  which  disappears  in  course  of  time, 
and  leaves  a  mass  of  feathery,  strongly  iridescent  crystals, 
which  will  be  more  closely  investigated  hereafter. 
Samaderine  may  be  placed  in  the  series  of  indifferent,  crys- 
tallizable  organic  bodies,  to  which  salicine,  phloridzine,  &c, 
belong.  As  soon  as  it  has  been  prepared  in  larger  quantities, 
further  investigations  upon  it  shall  be  published ;  the  question 
will  then  also  be  solved,  whether  samaderine,  which  gives  so 
distinct  a  reaction  with  sulphuric  acid,  is  converted  thereby 
into  another  compound  and  grape-sugar,  like  salicine  and 
phloridzine. — London  Chem.  G-az.,  April  15, 1859,  from  Archiv 
der  Pharmacie. 
PREPARATION  OF  PLATINUM-BLACK. 
By  C.  Brunner. 
We  possess  several  methods  for  the  preparation  of  platinum 
in  that  state  which  is  usually  termed  platinum-Mac Jc,  on  account 
of  its  black  color.  In  most  of  the  recent  modes  of  preparation, 
organic  substances,  such  as  alcohol,  sugar,  &c,  are  employed  as 
reducing  agents,  by  which  means  there  is  always  a  doubt  whether 
a  certain  quantity,  perhaps  very  small,  of  organic  substance  may 
not  adhere  to  the  preparation. 
Perfectly  pure  platinum-black  may  be  very  easily  obtained 
in  the  following  way,  without  the  employment  of  any  organic 
substance: — 
Dry  peroxalate  of  iron  (prepared  by  precipitating  sulphate  of 
