^m.  Jour.  Pharin.  \ 
November,  1900.  J 
Technical  Chemistry. 
551 
eighth  of  the  soda  required  for  the  world's  consumption.  There  is 
even  some  possibility  that  hydrochloric  acid  may  be  made  even- 
tually by  uniting  electrolytic  chlorine  and  hydrogen.  The  principal 
electrolytic  processes  so  far  successfully  installed  are  the  Kastner- 
Kellner  mercury  method,  with  large  plants  at  Niagara  Falls  and  in 
England,  the  Hargreaves-Bird  process,  using  an  asbestos  diaphragm, 
with  a  considerable  plant  at  Liverpool,  and  the  large  works  at  Leo- 
poldschall.  The  plant  at  Rumford  Falls,  Me.,  using  platinum  elec- 
trodes, went  out  of  operation  during  the  year.  Probably  the 
momentum  of  large  capital  invested  in  the  chamber  acid  plants  and 
in  the  LeBlanc  soda  process  will  maintain  for  both  a  more  or  less 
profitable  existence  for  a  number  of  years  to  come,  in  spite  of  all 
competition. 
The  great  change  in  the  chlorate  industry  has  already  been  re- 
ferred to.  Practically  all  that  in  use  is  now  made  by  electrolysis. 
There  has  been  a  marked  decrease  during  the  year  in  American 
imports  of  chlorate,  soda  and  caustic,  due  to  the  installation  of  large 
ammonia-soda  works  at  Syracuse,  Detroit  and  Bay  City,  and 
another  large  works  is  now  under  construction  at  Barberton. 
The  manufacture  of  calcium  carbide  has  grown  during  the  year 
to  immense  proportions,  but  with  a  maintenance  of  prices,  showing 
a  large  increase  in  its  use.  In  Germany  nearly  all  of  the  railway 
coaches  are  now  lighted  by  a  mixture  of  one-third  acetylene  and 
two-thirds  Pintsch  gas,  resulting  in  both  an  increase  of  light  and 
decrease  of  cost. 
Another  product  of  the  electrical  arc  furnace  which  has  been 
largely  manufactured  during  the  past  year  and  has  found  an  even 
larger  demand  is  graphitized  electrolytic  carbons.  It  is  found  that 
when  ordinary  pressed  carbons  are  packed  in  charcoal  and  placed  in 
the  path  of  a  large  electrical  current  so  as  to  be  intensely  heated 
for  a  considerable  time,  the  carbon  of  which  they  are  composed  is 
practically  converted  into  graphite.  Such  graphitized  carbons, 
owing  to  the  uniform  texture  which  they  are  given,  and  to  the 
higher  power  to  resist  oxidation,  are  found  to  have  two  or  three 
times  the  life  of  ordinary  carbons  for  all  electrolytic  purposes,  and 
their  use  js  rapidly  growing. 
In  the  manufacture  of  wood  spirits  a  greater  purity  of  product 
has  been  brought  about  by  greater  care  in  fractioning.  Also  many 
new  externally  heated  retort  plants  are  replacing  old  kiln-furnaces 
