VARIETIES. 
569 
baiie  ties 
Soda. — This  is  a  most  important  manufacture.  Few  changes  in  the 
principle  of  manufiicture  have  taken  place  during  the  last  ten  years,  the 
essential  points  of  the  original  method  of  Leblanc  (1798)  being  still  ad- 
hered to.  The  extent  of  the  manufacture  has  largely  increased  since  the 
year  1851.  The  value  of  alkali  made  annually  in  England  is  2,000,000Z.  ; 
of  this  half  is  made  in  South  Lancashire  and  half  in  the  Newcastle  district. 
The  following  statistics  apply  to  the  South  Lancashire  alkali  trade,  per 
week,  in  1861 : — Common  salt  decomposed  per  week,  2600  tons  ;  sulphuric 
acid  used,  3110  tons  :  soda  ash  sold  per  week,  1800  tons  ;  salt  cake  sold 
per  week,  180  tons  ;  soda  crystals  ditto,  170  tons;  bicarbonate  soda  ditto, 
225  tons  ;  and  caustic  soda  ditto,  90  tons.  Since  1852  the  alkali  tradeof 
South  Lancashire  had  more  than  tripled.  The  large  quantity  now  pro- 
duced was  manufactured  in  about  twenty-five  works,  chiefly  situated  at  St. 
Helen's,  Runcorn  Gap,  Widnes  Dock,  near  Warrington,  the  neighborhood 
of  Bolton,  and  Newton  Heath.  None  of  the  patents  for  improving  the 
manufacture  of  alkali  had  changed  the  process  materially.  The  improve- 
ments of  detail  since  1851  have  been  the  following  : — 1.  Greater  attention 
to  economical  working  in  all  the  branches.  2.  The  process  of  lixiviation 
of  black  ash  is  more  completely  accomplished  than  formerly  by  the  ar- 
rangement of  Mr.  Shanks.  3.  In  some  works  the  black  ash  is  now  made 
by  machinery.  4.  The  soda  is  now  in  many  alkali  works  packed  in  casks 
by  machinery.  Since  1851,  a  new  branch  of  the  manufacture  has  been 
introduced  by  the  preparation  of  solid  caustic  soda,  which  is  largely  ex- 
ported to  America  and  other  places.  The  proposition  recently  made  by 
Kuhlmann  for  the  employment  of  the  alkali  waste  as  a  cement  is  a  very  old 
idea,  Mr.  Deacon,  of  Widnes,  having  used  it  for  making  floors  for  twenty 
years.  In  conclusion,  the  report  recognised  the  important  additions  to 
our  knowledge  of  the  theory  of  soda  manufacture  made  by  Mr.  Gossage. 
— London  Chem.  News,  Sept.  21,  1861. 
New  Formulae  for  Sinapisms. — M.  Grimault  recommends  the  following 
formulae  : — Pure  Glycerine  3^  drachms,  starch  5  drachms,  and  volatile  oil 
of  mustard  20  drops  ;  and  M.  Clievallier  publishes  the  following  formula 
for  what  he  terms  Plastic  Sinapisms: — Volatile  oil  of  mustard  20  drops, 
white  pitch  15  drachms.  Having  melted  the  pitch,  remove  it  from  the  fire, 
stir  in  the  volatile  oil,  and  spread  on  leather.  By  the  addition  of  10  per 
cent,  of  resinous  oil,  the  mass  can  be  spread  on  linen  like  ordinary  adhe- 
sive plaster.  For  use,  a  piece  can  be  cut  ofi"  according  to  the  size  of  the 
part  to  which  the  sinapism  is  intended  to  be  applied.    The  efiect  is  very 
