Am,  Jour.  Pharm. 
Jan.,  1888. 
Aldehyde  Resin. 
29 
10  per  cent,  hydrochloric  acid  was  then  added,  and  after  48  hours  the 
crystals  of  uric  acid  thus  formed  were  filtered  off.  The  filtrate  was 
boiled  for  18  hours,  at  the  end  of  which  time  the  remains  of  the  uric 
acid  with  an  abundance  of  pigment  were  precipitated ;  the  filtrate  had 
an  orange-red  color  ;  to  this,  chalk  and  sodium  phosphate  were  added  ; 
the  bulky  precipitate  which  was  formed  carried  down  with  it  the  re- 
mains of  pigment.  The  precipitate  obtained  from  the  urine  by  boil- 
ing was  Avashed  with  cold  water,  hot  water,  alcohol  and  ether,  dissolved 
in  dilute  sodium  hydroxide  solution,  and  precipitated  by  sulphuric 
acid.  This  was  repeated  three  times,  and  the  final  product  was  a 
bright,  brownish-black  substance,  occurring  in  plates  but  easily  pow- 
dered. It  was  insoluble  in  cold  water,  dilute  alcohol,  ether,  and 
chloroform,  sparingly  soluble  in  warm  water,  absolute  alcohol,  light 
petroleum,  and  concentrated  sulphuric  and  hydrochloric  acids.  It  was 
easily  soluble  in  amyl  alcohol,  concentrated  ammonia,  but  especially 
in  solutions  of  potassium  or  sodium  hydroxide.  It  can  be  heated  to 
115°  without  decomposition ;  with  soda-lime  it  yields  ammonia;  on 
dry  distillation,  it  gives  a  smell  of  formic  acid,  and  after  complete 
combustion  leaves  a  minimal  amount  of  ash  which  contains  no  iron. 
The  average  quantity  in  which  it  occurs  in  urine  is  0*03  per  cent. 
By  the  action  of  potash,  it  yields  ammonia,  formic  acid,  acetic  acid, 
butyric  acid,  palmitic  acid  (?),  catechol,  protocatechuic  acid,  and  the 
residue  is  free  from  nitrogen,  and  has  the  following  percentage  compo- 
sition : — Carbon,  62*26;  hydrogen,  3'9 ;  and  oxygen,  33*84. 
ALDEHYDE  RESIN.^ 
By  E.  Puchot. 
Aldehyde  resin  washed  two  or  three  times  with  warm  water  and  ex- 
posed to  air  becomes  hard  and  friable.  It  dissolves  in  alcohol  and  is 
precipitated  by  water.  Analysis  of  two  preparations  gave  the  formula 
C^gHg^Oio  +  TiHgO,  n  being  equal  to  4,  but  the  amount  of  water  is 
variable.  When  exposed  to  dry  air,  the  resin  gives  ofP  water,  and  its 
weight  gradually  reaches  a  minimum  at  which  it  remains  constant  for 
some  time,  and  then  increases.    When  the  weight  is  at  the  minimum, 
^  Ann.  Chim.  Phys.  [6],  ix,  422.  Reprinted  from  Jour.  Chem.  Society,  1887,  p. 
1090. 
