322 
Varieties. 
f  Am.  Jour.  Pharm. 
t    July  1,  1872. 
drop  by  drop,  the  sulphuric  acid  to  be  tested,  the  vessel  being  agitated  at  each 
addition.  This  addition  will  cause  considerable  heating,  and  if  no  arsenic  is 
present  the  liquid  will  remain  clear.  If  the  arsenic  is  present  in  the  smallest 
quantities  the  liquid  will  be  colored  first  yellow,  then  brown,  and  finally  a  dark 
greyish-brown,  becoming  at  the  same  time  turbid. 
The  process,  while  far  more  readily  carried  out  than  Marsh's,  is  declared  to 
be  nearly  equal  to  it  in  delicacy. — Journal  Franklin  Institute,  June,  1872. 
A  New  Use  for  the  Aniline  Colors. — Mr.  F.  Springmiihl  recommends  the  use 
of  alcoholic  solutions  of  various  gums  (shellac,  sandarach,  &c),  to  which  various 
aniline  colors  have  been  added,  in  coloring  all  kinds  of  paper,  linen,  &c*. 
The  gum  solution,  which  should  be  thin,  penetrates  entirely  through  the 
paper  and  gives  to  it  an  even  tone.  The  operation  is  simply  to  place  the  coloring 
liquid  in  a  shallow  dish,  and  to  draw  the  substance  to  be  colored  through  it, 
which  is  subsequently  hung  up  to  dry  ;  when  dry  another  color  can  readily  be 
produced  upon  one  of  the  sides.  Sandarach  is  said  to  produce  matt;  shellac 
and  most  other  gums,  a  lustrous  color.  By  adding  to  the  lac  solutions  a  small 
quantity  of  some  ethereal  oil,  the  substance  may  at  the  same  time  be  perfumed. 
By  judiciously  mixing  several  of  the  lacs,  any  desirable  tint  can  be  produced. 
—  Journal  Franklin  Institute,  June,  1872. 
Hydrofluoric  Acid—  Mr.  A.  P.  S.  Stuart  remarks  that  every  one  who  has 
prepared  hydrofluoric]  acid  knows  that  sulphuric  acid  and  fluor  spar  form  an 
exceedingly  hard,  rock-like  compound,  and  that  it  is  very  difficult  to  remove 
this  from  a  platinum  retort.  The  inconvenience  may  be  avoided  by  mixing  with 
the  fluor  spar  about  an  equal  weight  of  gypsum  and  the  proper  quantity  of  sul- 
phuric acid.  After  the  hydrofluoric  acid  has  been  expelled  by  heat,  the  mass 
in  the  retort  is  found  to  be  of  a  pasty  nature,  and  is  easily  removed  by  water. — 
Scientific  American,  June  22,  1872. 
Action  of  Sulphuric  Ether  on  Iodides. — E.  Ferriere. — When  to  a  solution  of 
any  iodide  in  water  there  is  first  added  some  starch  solution,  and  this  mixture 
shaken  up  with  sulphuric  ether,  the  following  phenomena  are  observed  :  If  the 
solution  of  the  iodide  is  somewhat  concentrated,  a  portion  of  iodine  is  set  free, 
and  the  starch  is  colored  blue  ;  if  the  solution  is  weak,  this  coloration  only  sets 
in  after  some  three  hours;  if  the  solution  is  very  dilute,  the  blue  coloration 
only  appears  after  some  two  or  three  days.  When  the  blue-colored  starch  is 
separated  by  filtration,  and  there  is  added  to  the  filtrate  another  dose  of  ether, 
the  blue  coloration  again  appears,  all  the  iodine  being  at  last  driven  from  its 
combination  ;  chlorides  and  bromides  are  not  thus  acted  upon.  The  author 
attributes  this  decomposition  to  the  slow  but  continuous  formation  of  an  unsta- 
ble iodhydric  ether  (C4  H5  I),  but  the  experimental  proof  of  that  reaction  has 
not  been  found  by  him. —  Chem.  News.  May  31,  1872. 
Apomorphine — A  New  Remedy. — It  appears  that  the  Materia  Medica  is 
about  to  be  enriched  by  an  important  remedy — apomorphine,  an  emetic  appa- 
*  Zeitschr.  f.  Farberei,  1871,  No  41. 
