494  The  different  Syrups  of  the  Phosphates.  {AmJ0Tj^rm- 
Mix  the  acid  and  water,  and  dissolve  the  lime  in  the  mixture.  Filter 
the  solution. 
Crystallized  sodic  carbonate,        .  .       54  grains  5 
Potassic  carbonate,  .  .  72  grains ; 
Phosphoric  acid  (sp.  gr.  1*75),     .  .         \  oz.  by  weight; 
Distilled  water,      ...  1  fluidounce. 
Dissolve  and  filter.  Then  mix  all  the  solutions,  and,  having  added 
distilled  water  to  make  the  solution  measure  28  fluidounces,  dissolve  in 
it  with  heat  sugar,  3J  lb.  ;  powdered  cochineal,  85  grains  ;  and  strain 
while  hot.  When  cold,  add  orange-flower  water,  2  fluidounces,  and 
sufficient  distilled  water  to  make  the  whole  measure  64  fluidounces. 
The  product  is  a  nice  clear  syrup,  entirely  free  from  sulphate  of  soda 
or  ammonic  chloride,  both  of  which  are  by  no  means  uncommon  im- 
purities, from  the  difficulty  of  washing  the  precipitates  when  the  syrup 
is  made  in  the  old  way,  while  the  whole  process  will  be  found  very 
much  less  troublesome  and  tedious.  Calcic  hydrate  is  generally  suf- 
ficiently pure  as  commonly  obtained,  though  where  the  chemist  has 
the  facilities  for  doing  it,  it  is  best  for  him  to  make  the  lime  himself, 
by  igniting  precipitated  chalk  in  a  crucible,  at  a  full  red  heat,  for  an 
hour. 
I  may  remark  here,  though  it  does  not  exactly  bear  on  the  subject, 
that  the  last  edition  (1872)  of  Pereira's  "Materia  Medica  "  contains 
the  astonishing  information,  on  page  213,  that  "  Hypophosphite  of  lime 
is  an  important  constituent  in  Parrish's  Chemical  Food  a  statement 
that  is  liable  to  mislead  physicians  in  a  serious  manner. 
Easton's  syrup  is  another  preparation  that  is  frequently  badly  made, 
and  very  often  deficient  in  iron.  The  precipitate  so  frequently  met 
with,  in  the  form  of  phosphate  of  quinia,  is,  I  think,  always  owing  to 
the  use  of  an  acid  containing  metaphosphoric  acid.  I  have  never  been 
troubled  with  a  precipitate  since  I  have  taken  pains  to  use  only  ortho- 
phosphoric  acid,  H3P04.  The  change  in  color  is  due  to  exposure  to 
the  air,  chiefly  from  oxidation  of  the  iron  salt,  but  partly  to  the  quinia 
changing  color.  It  may  be  entirely  avoided,  as  has  been  often  re- 
marked, by  completely  filling  the  bottles  in  which  the  syrup  is  kept, 
and  corking  so  as  to  have  as  little  air  left  in  the  bottle  as  possible. 
No  trouble  will  be  found  in  making  a  satisfactory  preparation  if  the 
following  form  be  strictly  followed,  and  care  taken  to  avoid  exposure  to 
the  air  of  the  iron  solution. 
