AmbJe0cU,ri8P79arin' }  Gleanings  from  the  Germvn  Fournals.  599 
utes,  while  all  impurities,  together  with  the  Irish  moss,  rise  to  the 
surface,  and  are  skimmed  off  or  removed  by  straining.  The  product 
does  not  contain  the  slightest  trace  of  tannin,  which  is  removed  as  an 
insoluble  compound  with  the  other  impurities. — Ibid.,  Oct.  4,  1879, 
p.617. 
Uses  of  Starch-sugar  in  Practical  Chemistry.  —  Starch-sugar, 
dissolved  in  soda  lye,  is  used  by  Boettger  for  reducing  the  soluble  and 
insoluble  silver-salts,  and  is  regarded  by  him  as  the  most  simple,  clean 
and  efficacious  agent  for  the  purpose.  Freshly  precipitated  and  washed 
silver  chloride,  in  a  porcelain  dish,  is  covered  with  soda-lye,  an  equal 
quantity  of  starch-sugar  is  added,  and  the  mixture  is  heated  to  the  boil- 
ing point,  when  the  reduction  will  be  effected  in  a  few  minutes. 
An  extraordinarily  efficacious  platinum  black  is  obtained  by  adding  to 
a  solution  of  platinum  chloride  in  water  caustic  soda  in  excess  and  a 
corresponding  quantity  of  starch-sugar,  and  boiling  the  whole  for  5  or 
10  minutes,  when  all  platinum  separates  as  a  velvety-black  powder. — 
Ztscbr.  d.  Allg.  Oest.  Ap.  Ver.,  Oct.  10,  1 879,  p.  430,  from  Jabresb. 
Phys.  Ver.,  Frankfurt. 
The  glucoses  of  different  origin,  as  sugar  from  honey,  from 
starch,  sugar  formed  by  the  decomposition  of  amygdalin  and  salicin, 
etc.,  are  all  considered  identical  by  Hesse,  not  only  in  regard  to  their 
optical  relation  but  also  in  regard  to  their  melting  point,  which,  in  the 
hydrate,  C6H1206+H20,  lies  between  80  and  84°C.  The  author 
noticed  a  separation  of  anhydrous  glucose  in  hard  prisms,  while  a 
syrupy  glucose  solution  was  crystallizing,  and  supposes  Anthon's  half- 
hydrate  to  have  been  a  mixture  of  anhydrid  and  hydrate. 
Pblorose,  the  sugar  formed  by  the  splitting  of  phlorrhizin,  has  the 
appearance,  reducing  power  and  contains  the  same  percentage  of  water 
as  glucose,  but  differs  in  melting  at  74°C,  and  polarizing  one-sixth 
weaker. — Ibid.,  Oct.  10,  1879,  p.  432,  and  Ann.  d.  Chem. 
Preparation  of  Butyric  Acid. — Dr.  Enders  recommends  the  fol- 
lowing process:  10  kilos  of  starch  are  mixed  with  5  kilos  of  chalk  in 
a  copper  kettle,  water  is  added  and  the  mixture  boiled  to  a  thick  paste. 
This  is  transferred  to  stoneware  or  wooden  vessels,  water  and  skimmed 
milk  are  added,  together  with  a  corresponding  quantity  of  putrid,  old 
cheese,  and  the  mixture  is  allowed  to  ferment  in  a  warm  place  ;  since 
the  chalk  is  uniformly  suspended  in  the  paste  frequent  stirring  is 
