318 
ON  ELECTRO-PLATING. 
but  no  facts  have  been  elicited  which  prove  it  to  be  so.  From 
my  own  experiments  on  this  subject,  I  am  induced  to  believe 
that  the  two  alkaloids  are  entirely  dissimilar  in  their  chemical 
composition. 
Sulphate  of  quinine,  dissolved  in  an  aqueous  solution  of 
chlorine,  and  a  few  drops  of  ammonia  added,  furnishes  a  deep 
green  color  characteristic  of  quinine.  Sulphate  of  quinidine 
treated  in  the  same  manner,  remains  colorless  if  free  from 
quinine. 
Sulphate  of  quinine,  dissolved  in  acetic  acid,  a  few  drops  of 
tincture  of  iodine  added,  the  mixture  heated  and  allowed  to 
cool,  furnishes  a  beautiful  emerald  green  crystalline  compound, 
called  sulphate  of  iodo-quinine  by  Dr.  Herepath,  its  discoverer. 
Sulphate  of  quinidine,  treated  in  the  same  manner,  furnishes  a 
broivn  precipitate. 
The  sulphate  of  quinine  used  for  the  above  experiments  was 
prepared  by  re-crystallizing  the  commercial  salt.  The  sulphate 
of  quinidine  was  prepared  from  a  sample  of  pure  quinidine,  re- 
ceived from  C.  Zimmer,  Frankfort-on-the-Maine.  The  first  being 
a  di-sulphate,  and  the  second  a  neutral  salt.  The  reaction  with 
chlorine  and  ammonia  being  entirely  independent  of  the  acid  or 
water  of  hydration,  this  test  alone  is  sufficient  to  prove  that 
quinidine  is  not  a  hydrate  of  quinine. — N.  Y.  Jour,  of  Phar- 
macy,  May,  1853. 
ON  THE  PRACTICAL  APPLICATION  OF  TUNGSTEN,  MOLYBDE- 
DENUM,  TITANIUM,  AND  SILICUM,  TO  ELECTRO- PLATING. 
By  M.  Junot. 
Tungsten. — M.  Junot  first  prepared  his  tungsten  baths  with 
tungstate  of  ammonia  dissolved  in  a  lye  of  carbonate  of  soda,  with 
the  addition  of  200  parts  of  cyanide  of  potassium  for  each  1,000 
parts  of  metallic  salt,  sufficient  water  being  added  to  bring  the 
solution  to  specific  gravity  1,050  to  1,055.  He  obtained  equally 
good  results  by  the  employment  of  sulphites  and  hypo-sulphites  of 
soda  or  ammonia.  Lastly,  however,  he  has  obtained  very  supe- 
rior results  by  the  employment  of  the  double  cyanides  of  tungsten 
and  sodium,  prepared  simultaneously  in  the  following  manner : 
A  hot  saturated  solution  of  oxide  of  tungsten  in  carbonate  of  soda 
