Am'jJa0^riS6arm'}      Gleanings  from  Foreign  Journals.  17 
and  becomes  turbid  on  adding  5  volumes  of  absolute  alcohol ;  the  ad- 
dition of  more  water  makes  a  clear  solution.  2.  A  10  per  cent,  solu- 
tion does  not  become  turbid  either  at  an  ordinary  or  elevated  tempera- 
ture on  adding  nitric  acid,  acetic  acid,  ferroeyanide  of  potassium  or 
saturated  solution  of  sodium  sulphate.  3.  Picric  acid  produces  yellow 
— tannic  acid,  ash-gray  flakes.  4.  Sulphate  of  copper  and  caustic 
potash  produce  a  violet  coloration.  5.  It  should  yield  not  more  than 
2  per  cent,  of  ash  when  incinerated.  6.  If  to  20  drops  of  a  1  per  cent, 
solution  of  peptone  5  drops  of  a  10  per  cent,  solution  of  calcium 
bichromate  are  added  no  turbidity  is  produced ;  if  the  mixture  becomes 
turbid  it  proves  the  presence  of  at  least  5  per  cent,  of  glutinous  matter. 
Solution  of  bichromate  of  calcium  (Freire's  test)  is  made  by  dissolving 
5  grams  crystallized  chromic  acid  in  25  grams  of  water,  gradually 
adding  2  grams  pure  calcium  carbonate ;  after  effervescence  the  solution 
is  diluted  to  60  c.c.  and  filtered  through  glass-wool.  Owing  to  the 
rapidity  with  which  peptone  is  decomposed  it  is  not  advisable  to  keep 
it  in  liquid  form. — Schweiz.  Wochenschrift,  xxiii,  p.  381. 
Potable  Water. — The  International  Pharmaceutical  Congress  adopted 
the  following  resolutions  in  reference  to  drinking  water:  1.  It  should 
be  clear,  transparent,  colorless,  odorless  and  free  from  suspended  matter, 
2.  It  must  be  fresh,  have  a  pleasant  taste,  and  a  temperature  not  over 
15°  C.  3.  It  should  contain  air  and  a  certain  amount  of  carbonic 
acid.  The  air  it  contains  must  contain  30-33  per  cent,  oxygen.  4.  It 
should  not  contain  more  than  20  milligrams  of  organic  matter  to  the 
liter  (determined  by  oxalic  acid)  and  should  be  free  from  nitrogen. 
5.  The  nitrogenous  organic  matter  oxidized  with  potassium  perman- 
ganate should  not  yield  more  than  0*1  milligram  albuminous 
nitrogen  to  the  liter.  6.  It  should  not  contain  more  than  0'5  milli- 
gram of  ammonia  in  each  liter.  7.  A  liter  of  water  should  not 
contain  more  than  0*5  gram  of  mineral  salts,  60  milligrams  anhydrous 
sulphuric  acid,  8  milligrams  chlorine,  2  milligrams  anhydrous  nitric 
acid,  200  milligrams  oxides  of  the  alkaline  earths,  30  milligrams 
of  silica  and  3  milligrams  of  iron.  8.  Drinking  water  should  not 
contain  any  nitrites,  sulphuretted  hydrogen  or  sulphides,  nor  should 
it  contain  any  metallic  salts  which  are  precipitated  by  sulphuretted 
hydrogen  or  ammonium  sulphide  excepting  traces  of  iron,  aluminium 
and  manganese.  9.  When  kept  in  closed  or  open  vessels  it  should 
not  acquire  a  disagreeable  odor.  10.  It  should  not  contain  any 
saprophytes,  leptotrix,  leptomites,  hypheotrix,  and  other  white  algae, 
