Am.  Jour.  Pharm. ) 
June,  1883,  J 
Lithim  Cit7'as. 
315 
macopoeia  in  1870,  also  in  the  revised  edition  lately  published,  and 
these  are  the  only  two  Pharmacopoeias  in  which  it  is  recognized. 
The  German  Pharmacopoeias  of  1872  and  1882  have  the  carbonate^ 
but  not  the  citrate,  and  the  same  is  the  case  with  the  French  Codex. 
The  instructions  for  making  this  salt  are  different  in  each  Pharma- 
copoeia. 
In  the  British  of  1864,  the  directions  are:  — 
Take  of 
Carbonate  of  lithia  50  grs. 
Citric  acid  in  crystals  90  grs. 
Warm  distilled  water   1  fl.  oz. 
Dissolve  the  citric  acid  in  the  water  and  add  the  carbonate  in  suc- 
cessive portions,  applying  heat  until  the  effervesence  ceases,  and  a  per- 
fect solution  is  obtained.  Evaporate  by  a  steam  or  sand  bath  until 
water  ceases  to  escape,  and  the  residue  is  converted  into  a  viscid  liquid- 
This  should  then  be  dried  in  an  air  •  oven  at  about  240°  F.,  then 
rapidly  pulverized,  and  enclosed  in  a  stoppered  bottle.  The  process, 
in  the  British  Pharmacopoeia  for  1867  is  exactly  the  same. 
In  the  United  States  Pharmacopoeia  for  1870,  we  find : — 
Take  of 
Lithium  carbonate  100  grs. 
Citric  acid  in  crystals  200  grs. 
Distilled  water   2  fl.  oz. 
Dissolve  the  citric  acid  in  the  water,  gently  heated,  and  to  the  solu- 
tion gradually  add  the  carbonate  until  perfectly  dissolved,  heating,  the 
mixture,  so  long  as  effervescence  is  produced.  Evaporate  by  means  of 
a  steam  or  sand  bath  to  a  viscid  consistence,  dry  the  residue  in  an  oven^. 
at  a  temperature  of  about  240°  F.,  then  rapidly  pulverize,  and  pre- 
serve in  a  stoppered  bottle. 
In  the  revised  Pharmacopoeia  of  the  United  States,  lately  issued,  no- 
process  is  given  in  accordance  with  the  decision  to  omit  processes  except 
where  necessary  to  insure  a  particular  result. 
Neither  the  proportions  of  the  British  Pharmacopoeia  nor  that 
of  the  United  States  Pharmacopoeia  are  correct,  for  the  former 
having  an  excess  of  carbonate  gives  an  alkaline  product,  whereas  the 
latter,  having  an  excess  of  citric  acid  gives  an  acid  product. 
As  Mr.  Umney  pointed  out  in  a  paper  read  at  the  Pharmaceutical 
Conference  of  1875,  if  the  formula — 
3  Li2C03+2(H3CeHA,H20)==2  LisC.Hp.  +  S  H2O  +  3  CO^ 
