AFebJr0uaryPi8a95m'}  Notes  on  Some  Saps  and  Secretions.  91 
Jackson's  pectoral  syrup,  although  the  odor  is  masked  by  the  pres- 
ence of  oil  of  sassafras. 
Even  simple  syrup  itself,  when  turning  somewhat  sour,  will 
have  the  odor  of  the  gas,  if  the  ultramarine  has  not  been  carefully 
removed. 
Of  inconvenience  this  fact  will  also  be  found  in  the  manufac- 
ture of  soda  syrups,  especially  those  containing  free  acid  or  acid 
fruit  juices. 
The  repulsive  odor  of  some  fruit  syrups,  after  undergoing  this 
decomposition,  is  thereby  explained. 
It  is  noticeable  at  times  that  the  ultramarine  in  syrups  containing 
free  acid  gradually  disappears  on  standing. 
The  pigment  is  usually  not  found  in  acid  syrups  prepared  by  heat, 
as  decomposition  of  the  blue  takes  place  more  rapidly  during  this 
procedure. 
Syrups  containing  free  alkali,  such  as  rhubarb  and  senega,  do 
not  evolve  sulphuretted  hydrogen,  as  the  ultramarine  remains  un- 
affected by  alkalies. 
Incidentally  the  recommendation  of  the  Pharmacopoeia,  to  prepare 
syrups  by  cold  percolation,  must  be  called  wise  and  practical.  If 
carefully  prepared  and  preserved,  it  not  only  obviates  the  possibility 
of  recrystallization  of  the  sugar,  but  will  also  remove  foreign  mat- 
ter, which  will  at  times  occasion  deposits  or  even  induce  fermenta- 
tion. 
In  the  presence  of  the  ultramarine  pigments  the  intervention  of 
the  sponge  will  remove  the  blue  in  neutral  or  alkaline  syrups. 
Even  if  it  should  be  decomposed  in  syrups  containing  acids,  the 
exposure  of  the  same,  being  yielded  drop  by  drop  in  the  course  of 
its  preparation,  should  be  sufficient  to  expel  all  appreciable  traces 
of  the  hydrogen  sulphide  gas. 
NOTES  ON  SOME  SAPS  AND  SECRETIONS  USED  IN 
PHARMACY  ~ 
BY  P.  Iy.  SlMMONDS,  F.L.S. 
There  are  very  many  of  these  which  deserve  special  detailed 
notice,  at  all  events  as  to  their  medicinal  uses  and  statistics. 
Four  subdivisions  might  be  established  under  which  all  the  varie- 
ties of  gums  and  resins  might  be  grouped  : 
