SOLUTION  OF  SULPHITE  OF  SODA. 
107 
ON  SOLUTION  OF  SULPHITE  OF  SODA. 
Prof.  Procter  : — ■ 
About  a  month  since  I  received  the  following  prescription,  the 
second  I  had  seen  of  the  kind,  and  which  I  think  has  frequently 
been  presented  at  the  counters  of  pharmaceutists  in  this  city : — 
Solut.  Sulphite  of  Soda  ^vj. 
S.  J. 
Take  two  teaspoonfuls  for  a  dose. 
Knowing  of  no  formula  for  such  a  preparation,  I  applied  in 
vain  to  several  apothecaries,  and  to  the  physician  himself,  to 
know  what  proportion  of  the  salt  indicated  was  to  be  dissolved 
in  a  given  quantity  of  water. 
Finding  that  the  secret  was  possessed  by  one  pharmaceutist 
only,  I  was  compelled  to  purchase  the  solution  of  him,  and  having 
taken  the  trouble  to  ascertain  its  composition,  I  thought  it  well 
to  communicate  the  result  in  this  way  ;  so  that  if  deemed  best 
it  may  be  made  public  through  the  columns  of  the  Journal,  for 
the  benefit  of  those  who,  like  myself,  have  been  at  loss  about  it. 
One  fluid  ounce  of  the  solution  being  evaporated  nearly  to  dry- 
ness, solidified  into  a  crystalline  mass  which  weighed  30  grains. 
On  examination  the  salt  possessed  the  properties  of  hyposul- 
phite of  soda;  it  was  odorless,  of  a  mild  saline,  "  hepatic"  taste. 
Heated  in  a  test  tube  it  fused  and  then  decomposed,  giving  off 
sulphur,  which  was  sublimed  into  the  upper  part  of  the  tube. 
The  solution  was  neutral  to  test  paper.  The  hyposulphite  is 
slightly  alkaline  unless  an  excess  of  acid  is  present.  Nitrate  of 
silver  caused  a  white  precipitate  soluble  in  excess  of  the  hypo- 
sulphite. This  precipitate  gradually  acquired  a  brown,  and 
afterwards  a  black  color,  owing  to  the  formation  of  sulphuret  of 
silver.  Freshly  precipitated  chloride  of  silver  was  also  entirely 
soluble  in  the  solution. 
This  salt  is  much  used  in  the  Dageurreotype  art  to  wash  off  the 
superfluous  iodine  from  the  plate.  Many  years  ago  it  was  highly 
recommended  as  an  antiherpetic,  and  used  as  a  remedy  in  exanthe- 
matous  affections,  painful  affections  of  the  skin,  slight  congestions 
of  the  viscera,  scrofula,  lymphatic  diseases,  &c.  A  formula  for 
a  syrup  of  the  hyposulphite  containing  one  part  of  the  salt  in  30, 
was  published  in  the  Journal,  Vol.  xvii. 
