Am.  Jour.  Pharm. 
Dec,  1887. 
Notes  on  Saccharin. 
623 
_taLi  (some  well  defined)  is  found  upon  the  cool  surface  of  the  appara- 
tus. These  ^cr^stalsj  except  for  a  slight  sweetness  of  taste,  correspond 
in  characters  and  tests  to  benzoic  acid.  The  sweet  flavor,  I  think, 
may  be  due  to  the  presence  of  a  very  small  quantity  of  undecomposed 
saccharin,  carried  mechanically  with  the  fumes.  The  escaping  vapors, 
which  are  very  irritable,  and  give  a  more  decided  odor  of  hydride  of 
benzol  than  the  powder  itself,  also  communicate  a  very  distinct  sensa- 
tion of  sweetness  to  the  back  part  of  the  palate.  Heated  over  the 
flame,  with  free  access  of  air,  saccharin  carbonizes  and  burns  with  a 
dull  yellow  smoky  flame,  leaving  a  residue  amounting  to  0*65  per 
cent,  of  sodium  salts.  It  does  not  reduce  an  alkaline  copper  solution, 
but,  like  gylcerin,  liberates  boracic  acid  from  borax,  the  latter  salt 
dissolving  saccharin  readily  in  aqueous  solution,  due  no  doubt  to  a 
displacement  of  the  boracic  acid. 
The  strong  acids,  either  hot  or  cold,  show  no  characteristic  color  re- 
action ;  the  compound  enters  solution  at  the  boiling  point  of  the  acid, 
arid  in  the  case  of  hydrochloric,  shows  a  white  granular  separation  on 
cooling.  Sulphuric  acid  develops  an  uncharacteristic  light-brown 
color. 
The  compound,  like  most  of  the  organic  acids,  shows  a  characteristic 
reaction  with  ferro-  and  ferrid -cyanide  of  potassium.  In  the  former 
case  no  change  is  perceptible  until  boiled,  when  a  greenish-white  tur- 
bidity appears  with  the  liberation  of  small  quantities  of  hydrocyanic 
acid.  In  the  latter  case  a  trace  also  of  this  acid  is  set  free,  with  the 
formation  of  a  very  distinct  green  solution,  the  latter  reaction  being 
very  perceptible  with  a  few  drops  of  a  1  in  1000  solution  of  saccharin 
in  water.  Heated  with  lime  very  distinct  odors  of  benzoic  aldehyde 
are  developed. 
Saccharin  possesses  very  decided  acid  properties,  and  combines  very 
readily  with  alkalies  or  alkaline  carbonates,  forming  anhydro-ortho- 
sulphamine-benzoates  of  the  same,  in  the  latter  case  at  the  expense  of 
the  carbonic  anhydride,  causing  strong  effervescence.  These  combina- 
tions are  very  soluble  in  water,  the  alkaline  carbonate  thus  forming  a 
ready  medium  for  the  solution  of  this  acid,  which  alone  is  so  sparingly 
soluble.  Another  advantage  of  some  importance  is,  that,  while  the 
harshness  of  flavor  perceptible  in  a  simple  solution  of  the  acid  is  de- 
stroyed, the  great  sweetness  appears  to  be  distinctly  intensified  and 
refined. 
The  following  shows  the  solubility  of  saccharin  in  the  various 
