232 
MANUFACTURE  OF  AMMONIA,  ETC. 
solution  to  the  extent  of  .00125 ;  and,  finally,  that  the  strongest 
solution  of  ammonia  which  it  is  possible  to  prepare  at  the  tempe- 
rature of  62°  Fahr.,  contains  in  an  imperial  gallon  of  solution 
one  hundred  test-atoms  of  ammonia. 
The  ammonia  meter  is  accompanied  by  a  table,  containing  six 
columns  of  numbers.  The  first  column  shows  the  specific  gravity 
of  the  solutions ;  the  second  column  the  weight  of  an  imperial 
gallon  in  pounds  and  ounces ;  the  third  column  the  percentage  of 
ammonia  by  weight ;  the  fourth  column  the  degree  of  the  solu- 
tion, as  indicated  by  the  instrument,  corresponding  with  the 
number  of  test-atoms  of  ammonia  present  in  a  gallon  of  the  liquor ; 
the  fifth  column  shows  the  number  of  grains  of  ammonia  con- 
tained in  a  gallon  ;  and  the  sixth  column  the  atomic  volume  of 
the  solution,  or  that  measure  of  it  which  contains  one  test-atom 
of  ammonia.  For  instance,  one  gallon  of  liquid  ammonia,  sp. 
grav.  880  weighs  8  lbs.  12.8  oz.  avoirdupois,  its  percentage  of 
ammonia,  by  weight,  is  33.117,  it  contains  96  test  atoms  of  am- 
monia in  one  gallon,  and  20400.0  grains  of  ammonia  in  one  gal- 
lon; and,  lastly,  104.16  septems  containing  one  test  atom  of  am- 
monia. Although  no  hydrometer,  however  accurately  constructed, 
is  at  all  equal  to  the  centigrade  mode  of  chemical  testing,  yet 
the  Ammonia  Meter  and  the  table  accompanying  it,  will  be  found 
very  useful  to  the  manufacturer,  enabling  him  not  only  to  deter- 
mine the  actual  strength  of  any  given  liquor,  but  the  precise 
amount  of  dilution  necessary  to  convert  it  into  a  liquor  of  any 
other  desired  strength,  whilst  the  direct  quotation  of  the  number 
of  grains  of  real  ammonia  contained  in  a  gallon  of  solution  of 
any  specific  gravity,  will  enable  him  to  judge  at  a  glance  of  the 
money-value  of  any  given  sample  of  ammonia. — Pharm.  Journ. 
Sept.,  1853. 
CONSTITUTION  OF  THE  "MELT"  OBTAINED  IN  THE  MANU- 
FACTURE OF.  FEREOCYANIDE  OF  POTASSIUM. 
Liebig  is  of  opinion  that  the  raw  product  of  melting  contains 
no  ferrocyanide,  but  only  cyanide  of  potassium,  while  Gmelin, 
Bunge,  and  others,  adopt  a  contrary  view.  The  results  refer- 
ring to  the  subjects  which  have  hitherto  been  obtained,  are  very 
contradictory,  and  for  this  reason  Reimann  has,  at  the  sugges- 
