556  Manufacture  of  Carbonate  of  Soda,  etc.  { AVe°cUR{,  188* 
sing's  process  were  designed  by  Engineer  E.  Rolland,  director  of  the 
tobacco  factory.  In  1855  a  company  was  organized  to  work  this  pro- 
cess. An  experimental  manufactory  was  started  at  Puteaux,  near- 
Paris,  but  owing  to  its  situation  and  arrangements  as  well  as  to  the 
salt  monopoly,  it  could  not  produce  soda  cheap  enough  to  compete 
with  the  other  process,  and  hence,  in  1858,  the  experiment  was  aban- 
doned. Schlcesing  and  Rolland  were  of  the  opinion  that  sooner  or 
later  the  new  process  must  come  into  use  in  making  soda. 
It  must  here  be  noticed  that  in  1858  Prof.  Heeren,  of  Hanover,, 
subjected  the  ammonia  process  to  a  very  careful  test  in  his  laboratory.. 
From  his  experiments  and  calculations  it  was  ascertained  that  this 
process  was  better  adapted  to  the  manufacture  of  bicarbonate  than  of 
the  simple  protocarbonate  of  soda. 
To  render  this  sketch  more  complete  and  historically  true,  it  must 
be  mentioned  that  T.  Bell,  of  England,  took  out  a  patent  Oct.  13^ 
1857,  for  a  new  soda  process,  which  in  principle  and  practice  was  al~ 
most  literally  the  same  as  that  of  Dyer. 
It  was  known  when  the  jury  was  working  at  Paris  in  1867  that  • 
essential  improvements  had  been  introduced  into  the  ammonia  process- 
by  the  efforts  of  Margueritte  and  de  Sourdeval,  of  Paris,  and  James 
Young,  of  Glasgow.  A  more  important  fact,  however,  is  that  Solvay 
&  Co.,  of  Conillet,  in  Belgium,  actually  exhibited  at  the  Paris  Expo- 
tion  carbonate  of  soda  prepared  by  this  new  process. 
Since  that  time  the  ammonia  process  has  been  developed  and  per- 
fected to  such  an  extent,  especially  by  Solvay,  Honigmann  and  Ger- 
stenhcefer,  that  as  early  as  February,  1873,  Prof.  A-  W.  Hofmann,  in 
his  introduction  to  the  third  group  of  the  catalogue  of  the  Exhibition 
of  the  German  Empire,  was  able  to  make  this  remark :  "At  all  events 
the  ammonia  process  is  the  only  one  which  threatens  to  become  an 
important  competitor  of  the  now  almost  exclusively  employed  process 
of  Leblanc."  The  Vienna  Exposition  has  since  proved  the  truth  of 
his  assertion. 
There  are  now  large  soda  works  in  England,  Hungary,  Switzerland,. 
Westphalia,  Thuringia  and  Baden,  which  employ  the  improved  am- 
monia  process,  and  some  of  them  make  fifteen  tons  of  soda  per  day. 
The  advantages  of  the  new  process  over  that  of  Leblanc  are  very 
evident,  although  the  details  of  the  process  have  not  yet  been  made 
public.  The  chief  advantage  consists  in  the  direct  conversion  of  salt 
into  carbonate  of  soda,  and  next  in  the  fact  that  from  a  saturated 
