86 
VARIETIES. 
Manufacture  of  Iodine. — To  the  Editoi  of  the  Chemical  News.  Sir  :  I  have 
been  a  subscriber  to  the  Chemical  News  for  many  years.  In  No.  364  I 
read  an  inquiry  for  the  names  of  manfacturers  of  iodine.  Perhaps  it  may 
serve  the  purpose  of  your  correspondent  to  know  that  in  this  city,  where 
more  than  nine-tenths  of  all  the  iodine  produced  in  Great  Britain  is  manu- 
factured, there  are  only  four  works — 
Annual  Produce. 
One  producing  about        .         .        20  kegs  of  112  lbs.  each 
One        "        "  .  100        «  « 
One        "        "  .  150        "  " 
One  (my  own  manufactory)        .     1000        "  " 
In  all,  1270 
Should  this  information  be  what  your  correspondent  wants,  he  is  wel- 
come to  use  it.  Yours,  &c,  Wm.  Patterson. 
Glasgow,  Nov.  26. 
—  Chem,  News,  Nov.  30,  1866. 
A  process  has  been  discovered  by  which  india  rubber  can  be  bleached 
to  a  pure  white,  and  after  having  been  hardened  will  be  used  for  collars 
and  cuffs.  It  is  a  difficult  one,  which  has  long  been  sought  for,  and  is  done 
by  a  chemical  process,  which  is  said  to  be  fatal  to  the  workmen  engaged 
therein  unless  protection  is  afforded  them. — Journal  of  Applied  Chemistry, 
Nov.,  1866. 
India  Rubier  Varnish. — That  India  rubber  dissolved  in  various  liquids 
yields  a  good  varnish  is  well  known  ;  but  in  general  they  are  too  viscid 
for  delicate  purposes,  and  are  only  good  for  making  stuffs  water-proof. 
India  rubber  liquefied  by  heat,  dissolved  in  oil  or  coal  tar,  or  drying  lin- 
seed oil,  does  not  give  a  varnish  of  sufficient  fluency  or  free  from  smell. 
Moreover,  a  considerable  quantity  of  India  rubber  remains  undissolved  in 
a  gelatinous  state,  suspended  in  the  liquid,  ro  that  the  solution  is  never 
clear.  Dr.  Bolly  has  recently  published  some  remarks  on  the  subject 
which  may  be  useful.  If  India  rubber  be  cut  into  small  pieces  and  di- 
gested in  sulphuret  of  carbon,  a  jelly  will  be  formed  ;  this  must  be  treated 
with  benzine,  and  thus  a  much  greater  proportion  of  caoutchouc  will  be 
dissolved  than  would  be  done  by  any  other  method.  The  liquid  must  be 
strained  through  a  woolen  cloth,  and  the  sulphuret  of  carbon  be  drawn  off 
by  evaporation  in  a  water  bath  ;  after  which  the  remaining  liquid  may  be 
diluted  at  will  with  benzine,  and  frequently  shaking  the  bottle  which  con- 
tains it.  The  jelly  thus  formed  will  partly  dissolve,  yielding  a  liquid 
which  is  thicker  than  benzine,  and  may  be  obtained  very  clear  by  filtration 
and  rest.  The  residue  may  be  separated  by  straining,  and  will  furnish  an 
excellent  water-proof  composition.  As  for  the  liquid  itself,  it  incorporates 
easily  with  all  fixed  or  volatile  oils.    It  dries  very  fast,  and  does  not  shine 
