PHARMACEUTICAL  GLEANINGS. 
317 
dissolving  an  ounce  of  protpsulphate  of  iron  in  six  ounces  of 
water,  and  adding  to  the  solution  an  ounce  of  sulphate  of  quinia 
and  a  few  drops  of  sulphuric  acid  to  dissolve  it.  This  solution  is 
filtered,  evaporated  till  a  pellicle  forms,  and  on  cooling  affords 
prismatic  crystals  of  the  double  salt,  strongly  bitter,  styptic,  and 
white,  very  soluble  in  water  and  alcohol,  and  possessing  an  acid 
reaction. 
Dr.  Regnoli  has  employed  this  new  product  in  several  cases  of 
cholera  with  great  success. 
Soluble  Citrate  of  Magnesia. — M.  E.  Robiquet  [Jour,  de  Chim. 
Med.)  suggests  the  following  formula  and  manipulation  to  pro- 
duce a  soluble  citrate  of  magnesia  : 
Take  of  Citric  acid,  a  kilogramme,  (35J  oz.,  avoir.) 
Carbonate  of  magnesia,  630  grammes,  (21J  oz..  "  ) 
Boiling  water,  350  grammes,  (10|  oz.,     "  ) 
Reduce  the  citric  acid  to  coarse  powder  and  dissolve  it  in  the 
boiling  water.  When  the  solution  is  cold,  and  before  it  crys- 
tallizes, pour  it  into  a  wide  earthen  vessel,  and  by  means  of  a 
seive  distribute  the  carbonate  of  magnesia  evenly  and  rapidly 
over  its  surface  without  stirring.  The  reaction  takes  place  little 
by  little  ;  when  it  ceases,  beat  the  mixture  rapidly  as  possible  so 
long  as  it  retains  its  pasty  consistence.  It  is  absolutely  neces- 
sary to  prevent  the  mixture  from  becoming  heated,  because  if 
the  temperature  rises  quickly  it  is  a  certain  sign  that  the  citrate 
of  magnesia  has  changed  its  molecular  condition  and  become  in- 
soluble. For  this  reason  it  is  safer  to  set  the  earthen  dish  in  a 
vessel  of  cold  water,  and  to  spread  out  the  citrate  on  the  sides  of 
the  dish.  When  this  manipulation  is  finished,  the  whole  is  al- 
lowed to  repose  during  24  hours,  divided  into  masses  and  dried 
at  a  heat  not  exceeding  70°  Fahr.  It  will  be  found  that  the  chief 
secrets  of  success,  are  the  employment  of  the  smallest  possible 
quantity  of  water,  and  to  avoid  the  rise  of  temperature  at  the 
moment  of  combination,  which  is  the  result  of  a  change  of  state 
of  aggregation  of  the  salt,  and  not  to  the  reaction  between  the 
carbonate  and  citric  acid. 
Amianthus  as  a  substitute  for  charpie  or  lint  Dr.  Dumont, 
of  Monteux,  has  found  that  that  form  of  asbestos  called  Amian- 
thus may  be  employed  as  a  dressing  instead  of  scraped  lint. 
This  substance  is  soft,  permeable,  smooth  to  the  touch  and  its  in- 
