NEW  TEST  SOLUTION  FOR  SUGAR. 
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good  for  deodorizing  purposes.  The  crude  gives  a  greenish  so- 
lution, which  even  while  cold,  but  more  rapidly  and  completely 
upon  boiling,  passes  into  the  deep  red  so  characteristic  of  the 
permanganate,  and  is  fit  for  use. 
As  a  test  for  organic  matter  in  air  and  water,  its  accuracy  has 
been  called  in  question,  on  the  ground  that  it  does  not  attack 
all  kinds  of  organic  matter  with  equal  facility, — some,  as  starch, 
resisting  its  action  for  a  long  time.    It  must  be  admitted,  how- 
ever, that  it  is,  at  present,  the  only  practical  test  that  we  have, 
and  certainly  shows  very  rapidly  and  clearly  the  presence  of 
hurtful  organic  matter  in  water  or  in  air.    It  can  be  applied  by 
any  one,  it  being  only  necessary  to  use  a  weak  solution ;  the 
disappearance  of  the  color  indicates  the  presence  of  organic 
matter.    In  time  of  epidemics,  such  as  cholera  or  dysentery, 
this  test  might  be  of  much  value  in  singling  out  the  contami- 
nated from  the  pure  water.    It  is,  perhaps,  well  also  to  recall 
the  fact  that  this  test  forms  the  readiest  means  of  purifying  foul 
water.    If  added  until  the  water  acquires  a  permanent  faint 
pink  tinge,  we  are  certain  that  injurious  organic  matter  has  been 
destroyed.    Then,  as  Condy  suggests,  if  a  piece  of  clean  stick 
be  put  into  the  liquid,  or  if  a  little  tea  or  coffee  be  added,  the 
pink  color  will  disappear,  and  the  water  will  be  fit  for  use.  The 
very  small  amount  of  potassa  remaining  in  solution  could  not 
possibly  do  harm,  as  in  any  ordinary  case  it  would  not  amount 
to  one-hundreth  part  of  a  grain  to  the  gallon. — Med.  Times, 
Fhila.  Oct.  15,  1870. 
NEW  TEST  SOLUTION  FOR  SUGAR. 
J.  Loewe  recommends  the  use  of  glycerin  in  place  of  tartaric 
acid  for  the  preparation  of  an  alkaline  copper  solution  for  the 
detection  of  sugar.  Glycerin  entirely  prevents  the  precipitation 
of  oxide  of  copper,  and  the  solution  prepared  with  it  has  the  ad- 
vantage of  being  less  liable  to  alteration  when  kept  than  the 
tartaric  solution  is. 
To  prepare  a  test  liquid  of  this  kind  16  grams  of  sulphate  of 
copper  should  be  dissolved  in  64  parts  of  water ;  to  this  solution 
is  gradually  added  80  c.c.  of  soda  solution  (1*34  sp.  gr.),  then  6 
