124 
Why  do  Syrups  Spoil? 
[Am.  Jour.  Pharm^ 
I     March,  190L 
much  better.  Glucose  is  inadmissible  because  of  the  reasons  al- 
ready stated.  To  fully  appreciate  what  effect  the  presence  of  ultra- 
marine has  on  this  syrup,  it  is  only  necessary  to  boil  a  syrup  made 
from  ordinary  sugar  and  one  made  from  rock  candy.  That  made 
with  sugar  turns  brown  when  the  boiling-point  is  approached,  while 
that  free  from  ultramarine  may  be  boiled  for  a  long  time  without 
impairing  in  any  way  the  fine  green  tint,  of  the  syrup.  It  is  true 
that  the  particles  of  superheated  syrup  adhering  to  the  flask  or 
evaporating  dish  above  the  surface  of  the  liquid  may  carbonize  and 
impart  a  color  to  the  syrup  when  dissolved  in  the  latter,  but  the 
color  will  not  be  due  to  decomposition  of  the  syrup,  as  is  the  case 
when  a  sugar  syrup  has  been  used.  If  care  be  taken  to  avoid  the 
solution  of  the  carbonized  particles,  the  boiling  syrup  retains  its 
handsome  brilliant  green  color.  Nor  is  it  necessary  to  keep  any 
iron  wire  in  a  syrup  so  made,  as  recommended  by  some.  The 
syrup  may  even  be  freely  exposed,  and  does  not  require  to  be  kept 
in  well-filled  bottles  only,  or  in  small,  completely-filled  bottles. 
In  the  syrups  containing  hypophosphites,  we  have  again  readily 
changeable  salts  acted  upon  by  a  sulphide.  The  compound  syrup 
of  the  N.  F.  in  particular  spoils  rapidly  if  any  ultramarine  is  pres- 
ent, whereas  if  absent  the  syrup  keeps  perfectly. 
In  syrups  of  senega,  senna  and  rhubarb,  we  have  polygalic  acid, 
cathartic  acid  and  chrysophanic  acid  present,  respectively;  in  syrup 
of  wild  cherry,  hydrocyanic  and  tannic  acids;  in  syrup  of  black- 
berry root,  tannic  acid.  In  fact,  an  inspection  of  all  Pharmacopoeial 
syrups  will  show  that  there  are  but  few  which  do  not  contain  one  or 
more  constituents  imcompatible  with  and  fully  able  to  decompose 
ultramarine  blue. 
To  go  a  step  further,  syrups  are  valued  adjuvants,  and,  next  to 
water,  are  perhaps  more  largely  prescribed  than  any  other  prepara- 
tion. Syrups  are  thus  brought  into  contact  with  every  kind  and  vari- 
ety of  substance,  a  fact  which  in  itself  furnishes  sufficient  reason  for 
insisting  that  a  pigment-free  syrup  be  made  obligatory  in  the  next 
Pharmacopoeia  by  replacing  the  sugar  by  white  rock  candy. 
It  is  true  the  initial  expense  of  preparing  such  a  syrup  is  greater 
than  when  sugar  is  used,  because  rock  candy  itself  costs  somewhat 
more  than  sugar,  and  because,  since  it  contains  more  water  of 
crystallization  than  does  sugar,  more  of  it  must  be  used  to  obtain  a 
syrup  of  proper  density.    Notwithstanding  the  greater  first  cost, 
