GLEANINGS  FROM  THE  FRENCH  JOURNALS.  411 
uallj  SO  much  of  a  solution  of  5  grs.  pure  ferrocyanide  of 
potassium,  until  the  purple  color  has  changed  into  yellowish^ 
brown,  which  is  best  observed  in  a  drop  being  placed  upon  a 
white  surface.  The  quanlitj^  of  ferrocyanide  used  indicates  the 
relative  value. — (Schvv.  Zeit.  f.  Ph.  vi.  15.) 
Ilydrar gyro-iodide  of  Arsenic,  prepared  by  rubbing  together 
790  gr.  iodine,  470  arsenic,  and  101  mercury  with  a  lictle  alco- 
hol, must  be  protected  from  the  light  and  air,  otherwise  bin- 
iodide  of  mercury  separates  in  crystals,  arsenic  oxidizes  and 
iodine  is  sublimed.  Landerer  recommends  to  prepare  it  ex 
tempore  from  the  iodides  of  arsenic  and  mercury. — ^(Schw. 
Zeits.  f.  Ph.  vi.  33.) 
Recognition  of  Phosphates  in  urinary  deposits. — Landerer  re- 
commends for  this  purpose  to  boil  the  sediments  in  diluted 
nitric  acid,  and  add  molybdate  of  ammonia,  when  the  character- 
istic yellow  precipitate  of  phospho-molybdate  of  ammonia  ap- 
pears.— (Schw.  Zeits.  f.  Ph.  vi.  34.) 
Separation  of  Acetic  Ether  W,  Engelhardt  mixes  the  distil- 
late obtained  from  acetate  of  soda,  alcohol  and  sulphuric  acid, 
with  an  equal  weight  of  water,  and  dissolves  in  this  liquid  chlo- 
ride of  sodium  to  saturation,  after  previously  neutralizing  the 
free  acid  by  magnesia.  The  acetic  ether  separated  after  12 
hours,  has  a  spec.  grav.  of  -89,  and  requires  7  parts  of  water 
for  solution.— (Polyt.  Notizbl.  1860,  No.  23.  Schw.  Zeits.  f. 
Ph.  vi.  45.) 
GLEANINGS  FROM  THE  FRENCH  JOURNALS. 
By  the  Editor. 
On  the  influence  of  the  color  of  glass  bottles  on  their  contents, 
by  M.  Dumey  In  view  of  the  custom  now  in  vogue  of  employ- 
ing blue  glass  for  the  purpose  of  counteracting  the  effects  of 
light  on  chemical  and  organic  substances,  M.  Dumey  calls  at- 
tention to  the  fact,  that  such  glass  has  no  action  on  the  chemi- 
cal rays,  and  that  blue  glass  is  not  better  than  white  glass  for 
that  purpose.  But  excellent  results  are  obtained  when  red  glass 
is  employed,  as  the  most  easily  effected  substances  undergo  no 
