ON  FLUID  EXTRACT  OF  LEPTANDRA  VIRGINICA.  225 
phuric  acid,  diluted  with  three  times  its  weight  of  water,  put 
them  in  a  thin  dish,  and  heat  on  the  water-bath  for  half  a  day.* 
By  this  process  only  37.25  drachms  phosphate  of  lime  will  be 
decomposed  by  the  sulphuric  acid,  which  combines  with  the  lime  of 
these  37.25  drachms  to  form  sulphate  of  lime,  while  the  phosphoric 
acid  gets  free  and  keeps  the  other  twelve  drachms  of  phosphate 
of  lime  in  solution.  After  being  cooled,  I  separate  the  liquid 
from  the  sulphate  of  lime  by  means  of  a  press,  put  some  fresh 
water  to  the  residue  and  press  again,  and  so  a  second  time. 
Should  the  liquid  obtained  measure  more  than  twenty  fluid 
ounces,  I  evaporate,  let  it  cool,  and  afterwards  filter,  to  separate 
from  sulphate  of  lime,  which  might  have  crystallized  out.  In 
the  clear  liquid,  I  dissolve  now  the  phosphate  of  iron,  the  carbo- 
bonate  of  potash  and  soda  in  the  quantity  given  by  Mr.  Parrish, 
which  will  dissolve  readily  without  the  use  of  muriatic  acid  ;  and 
then  I  make  the  syrup  by  adding  and  dissolving  the  sugar. 
In  this  syrup  the  ingredients  are  all  in  the  proportion  that  the 
formula  demands ;  the  quantity  of  sulphate  of  lime  in  it  is  so 
little,  that  it  certainly  does  not  speak  against  this  method,  as  it 
cannot  interfere  with  the  medical  properties  of  the  phosphates. 
This  method,  by  making  the  preparation  of  so  valuable  a  com- 
pound as,  I  think,  the  syrup  of  phosphates  is,  a  great  deal 
cheaper,  is  an  item  of  no  little  importance. 
Louisville,  Ky.,  April  4,  1858. 
ON  FLUID  EXTEACT  OF  LEPTANDRA  YIRGINICA. 
By  Samuel  Campbell. 
The  remedial  properties  of  Leptandra  Virginica,  or  Culver's 
Physic,  having  of  late  attracted  considerable  attention  among 
the  members  of  the  medical  profession,  I  have  devised  a  formula 
for  a  fluid  extract,  and  offer  the  following  process,  together  with 
the  reasons  that  led  to  its  adoption.  According  to  the  Eclectic 
Dispensatory,  the  active  principle  is  resinous  in  its  character, 
*  The  monohydrate  of  sulphuric  acid  is  easily  made  by  heating  com- 
mercial acid  in  a  China  dish  on  the  sand  bath,  until  the  acid  begins  to 
evaporate. 
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