Am  Ai°riir;i877.rm  }     Solution  of  Citrate  of  Magnesium.  1 6 1 
ovate,  somewhat  trilobed  leaves,  and  by  the  two-beaked  burs.  It  is 
common  in  this  country,  particularly  west.  Closely  allied  to,  and 
perhaps  a  mere  variety  of  it,  is  the  X.  echinatum,  Murray,  which  is  mainly 
distinguished  by  its  larger  burs,  and  is  found  here  near  the  seashore,  in 
many  places  of  Mexico,  South  America  and  the  Old  World.  X, 
indicum,  Roxb.,  which  is  found  from  China  and  India  west  to  Egypt,  is 
likewise  very  similar  to  it.  Evidently  distinct  is  X.  catharticum,  H. 
B.  K.,  of  Ecuador,  with  ternate  spines  and  pinnatifid  leaves,  which 
are  hispid  above  and  tomentose  beneath.  The  herb  is  used  in  its 
native  country  as  a  cathartic  under  the  name  of  cazamaroucba. 
SOLUTION  OF  CITRATE  OF  MAGNESIUM, 
To  the  Editor  of  "American  Journal  of  Pharmacy 
Dear  Sir — On  perusing  the  March  number  of  the  journal,  I 
noticed  two  articles  on  solution  of  citrate  of  magnesium  \  one  in  par- 
ticular (by  John  W.  Watts)  attracted  my  attention.  He  states  that 
the  u  officinal  formula  is  liable  to  a  series  of  objections  in  regard  to 
preparation  and  preservation,  and  then  proceeds  to  give  a  formula 
requiring  450  grains  of  citric  acid  and  120  grains  of  calcined  magnesia, 
and  substituting  boiling  water  for  cold  water. 
I  think  Mr.  J.  W.  W.  must  have  mistaken  an  old  edition  of  the 
"Dispensatory"  for  the  u  Pharmacopoeia  "  of  1870,  for  the  formula 
in  the  latter  directs  400  grains  of  citric  acid,  and  magnesium  carbonate 
instead  of  calcined.  Regarding  his  reference  to  an  almost  rotten  pre- 
paration, I  would  like  to  ask,  Where  is  the  u  pharmacist  "  of  any  stand- 
ing who  will  dispense  a  decomposed  solution  ? 
During  my  experience  I  have  adopted  the  following  formula  as 
yielding  a  satisfactory  preparation,  and  one  that  will  remain  unchanged 
for  a  reasonable  length  of  time  (two  weeks)  :  Ten  troyounces  of 
citric  acid  is  dissolved  in  a  quart  of  hot  water,  five  troyounces  of  carb. 
magnesium  is  added,  and  the  whole  stirred  until  dissolved  \  it  is  then 
filtered  into  a  graduated  five-pint  bottle,  and  sufficient  cold  water  added 
to  make  three  pints.  This  is  enough  for  twelve  bottles.  Put  two 
fluidounces  of  syrup  of  citric  acid  in  each  bottle,  add  four  fluidounces 
of  the  solution,  nearly  fill  with  cold  water,  cork  and  label  the  bottles, 
and  place  on  a  shelf.  When  I  have  a  call  for  it,  I  remove  the  cork, 
add  forty  grs.  bicarbonate  potassium,  replace  the  cork  and  secure  it  with 
