ON  THE  REDUCTION  OF  CHLORIDE  OF  SILVER.  537 
As  the  mixture  of  charcoal  with  the  pulp  lessens  the  strength 
of  the  paper,  this  objection  must  be  removed  by  inserting  a 
piece  of  gauze  in  each  sheet  of  paper,  or  only  in  the  centre  of 
each  sheet  when  they  are  required  to  be  used  as  filters,  so  as  to 
strengthen  that  part  which  forms  the  point  of  the  filter. 
The  pulp  for  this  paper  may  be  made  of  hemp,  linen  or  cotton 
rags,  and,  for  especial  purposes,  woollen  or  silk  rags  may  be 
used.  All  the  materials  are  purified  as  much  as  possible  with- 
out the  aid  of  soap  or  alkaline  substances,  and  with  water  as 
free  as  possible  from  earthy  salts.  The  paper  is  made  of  differ- 
ent thicknesses,  and  may  be  used  for  wrapping  fish,  game  and 
flesh  that  is  to  be  sent  to  a  distance. — London  Pharm.  Journal, 
Aug.,  1858. 
ON  THE  APPLICATION  OF  STARCH  SUGAR  AS  A  REDUCING 
AGENT  FOR  CHLORIDE  OF  SILVER. 
By  Prof.  Rudolph  Bosttger,  of  Frankfort. 
Translated  by  Charles  Caspari. 
According  to  my  observations,  there  does  not  exist  a  plainer, 
cleaner,  and  more  effective  agent  for  the  reduction  of  chloride 
of  silver,  as  well  as  for  all  those  silver  salts  soluble  or  nonsolu- 
ble  in  water,  than  starch  sugar  under  the  subagency  of  carbo- 
nate of  soda,  caustic  soda,  and  caustic  potash. 
Take  a  sufficient  quantity  (about  two  parts)  of  carbonate  of 
soda,  dissolve  it  in  a  little  water,  and  mix  in  a  porcelain  dish 
with  one  part  of  freshly  precipitated  and  perfectly  edulcorated 
chloride  of  silver ;  then  add  a  quantity  of  starch  sugar,  equal 
in  weight  to  that  of  the  chloride  of  silver  ;  heat  to  the  boiling 
point,  and  in  a  few  minutes  you  will  have  the  satisfaction  to 
observe  the  process  of  reduction,  even  with  large  quantities  of 
chloride  of  silver.  After  this  process,  the  reduced  silver  will 
appear  as  a  very  fine  dark  gray  powder,  which,  on  account  of  its 
heaviness,  can  easily  be  purified  by  merely  pouring  distilled 
water  on  it  and  then  stirring  well.  When  ignited  in  a  dry  state, 
it  will  appear  as  a  loosely  coherent,  delicate  dim  white  spongy 
mass  of  the  most  perfect  purity.  Even  when  large  quantities 
of  chloride  of  silver  are  to  be  reduced,  this  method — on  account 
