Amsep?.?i876.rm"}    The  Chemical  Industry  of  Germany.  425, 
and,  in  most  cases,  to  the  influence  of  Boards  of  Health,  have  taken  up  the  utiliza- 
tion of  the  sulphurous  acid  formerly  escaping  in  enormous  quantities  into  the  air. 
The  residues  from  the  Laming-mixture  of  the  gas-works,  containing  large  amounts 
of  sulphur,  and  the  sulphur  obtained  from  the  soda  residues  are  also  utilized  with 
advantage  in  the  manufacture  of  sulphuric  acid.  The  ordinary  pyrites  ovens  being 
utterly  inapplicable  to  the  burning  of  these  substances,  it  has  been  sought  to  con- 
struct suitable  ovens  for  this  purpose,  and  it  is  especially  in  this  field  that  German 
technologists  have  introduced  important  improvements. 
The  introduction  of  the  Glover-tower,  first  used  in  England,  into  the  German 
sulphuric  acid  manufacture,  marks  a  further  progress.  The  use  of  the  same  allows 
not  only  of  a  greater  saving  in  the  employment  of  nitric  acid,  but  renders  it  possible 
to  apply  the  heat  of  the  hot  sulphurous  acid  from  the  washing-ovens  to  concentra- 
tion of  the  sulphuric  acid. 
From  the  remaining  chemical-technological  products  of  the  major-industry  there 
remain  to  be  mentioned,  nitric  acid,  yellow  prussiate  of  potash,  alum,  aluminium- 
sulphate,  acetic  acid  and  oxalic  acid. 
The  nitric  acid  has  found  increased  application  by  its  use  in  the  manufacture  of 
anilin  and  alizarin-colors,  as  well  as  by  the  increased  production  of  sulphuric 
acid,  nitro-glycerin,  and  gun-cotton.  Of  the  salts  of  this  acid,  the  potassium 
compound  is  by  far  the  most  important.  It  is  made  in  Germany  almost  entirely  by 
decomposition  of  sodium  nitrate  with  potassium  chloride. 
The  yellow  prussiate  of  potash,  the  starting  point  of  the  other  cyanogen  com- 
pounds, finds  manifold  application  as  such  in  the  production  of  blue  colors  or,  in 
the  form  of  potassium  cyanide,  in  the  most  various  branches  of  industry.  The  use 
of  Berlin-blue  having  become,  however,  confined,  the  manufacture  of  the  yellow 
prussiate  of  potash,  in  Germany  especially,  since  animal  refuse,  owing  to  the  increased 
demand  for  manures,  has  risen  in  price,  has  made  but  little  progress.  The  many 
attempts  to  produce  the  nitrogen  of  the  cyanogen  compounds  from  other  than 
animal  sources  have  as  yet  not  given  results  of  practical  value. 
The  manufacture  of  alum  and  aluminium  sulphate,  which  have  an  extended 
application  in  dyeing,  cloth-printing  and  tawing,  as  well  as  in  paper-making,  has 
remained  as  well  as  unchanged,  except  that  ammonia  has  been  substituted  in  the 
alum  in  place  of  the  potash. 
Oxalic  acid,  which  a  few  years  ago  was  almost  entirely  an  English  monopoly,, 
has  lately  become  the  object  of  an  extended  manufacture  in  Germany.  The  oxalic 
acid  produced  in  Germany  leaves  nothing  to  be  desired  as  regards  its  quality,  and 
can  confidently  compete  with  the  English  product. 
The  oxidation  of  alcohol  on  the  one  side  and  the  distillation  of  wood  on  the 
other,  remain  the  methods  for  the  wholesale  manufacture  of  acetic  acid  and  the 
many  salts  of  it,  finding  application  in  technology. 
For  the  production  of  lead  acetate,  the  acetic  acid  from  alcohol  is  used  almost 
exclusively,  as  the  latter,  when  intended  for  this  branch  of  industry,  enjoys  indem- 
nity from  duty,  and  hence,  without  difficulty,  can  compete  with  the  pyroligneous 
acid.  It  is  different,  however,  with  the  other  acetic  acid  preparations,  in  whose 
production  the  alcohol  employed  is  not  free  from  duty.  The  present  unusually  low 
price  of  alcohol  alone  renders  it  possible  to  maintain  a  competition  with  the  acetic, 
acid  products  made  from  pyroligneous  acid. 
