238  Chloral  Hydrate  and  Camplior. 
103*5  grams  potassafor  one  kilogram  of  dry  herb. — Journ.  de  Pharm. 
et  de  Chim.,  1871,  April,  p.  285. 
Ointment  for  prurigo. — Norwegian  tar  15  grams,  Rousseau's  laud- 
anum* 2  grams,  lard  60  grams.  Mix.  To  be  used  morning  and 
evening.    Dr.  Girou  de  Buzareingnes. — Ibid.  p.  299. 
lodated  Sprup  of  Coffee. — Dr.  Calvo  recommends  syrup  of  coffee 
as  the  best  vehicle  for  disguising  the  taste  of  iodide  of  potassium,  and 
proposes  for  the  administration  of  this  salt,  a  syrup  made  by  dissolving 
16  grams  of  the  iodide  in  500  grams  of  syrup  of  coffee.  Dose,  a  table- 
spoonful,  twice  or  thrice  daily. — Ibid.  p.  299. 
CHLORAL  HYDRATE  AND  CAMPHOR. 
By  J.  F.  Brown. 
When  camphor  in  fine  powder  is  rubbed  in  a  mortar  with  an  equal 
weight  of  pure  crystallized  hydrate  of  chloral,  the  mass  becomes 
damp,  and  slowly  dissolves  to  form  a  syrupy  liquid,  strongly  resem- 
bling glycerin  in  appearance. 
A  rise  in  temperature  of  about  three  degrees  Fahr.  accompanies 
this  change,  showing  that  a  chemical  reaction  of  some  kind  must 
evolve  heat  more  than  sufficient  to  counterbalance  the  loss  of  sensible 
heat  which  always  attends  the  passage  of  a  substance  from  the  solid 
to  the  liquid  state. 
No  acid  or  irritating  fumes,  however,  were  perceptible  during  the 
solution,  and  the  resulting  liquid  was  neutral  to  test  paper.  i 
It  was  unaffected  by  solution  of  silver  nitrate,  left  a  greasy  stain 
when  dropped  upon  paper — permanent  for  some  hours — and  retained 
the  taste  and  smell  of  its  components. 
A  slip  of  paper  dipped  into  it  did  not  ignite  very  quickly  when 
brought  near  a  light,  but  burnt  with  a  bright  white  flame,  having 
emerald  green  edges. 
It  was  readily  soluble  in  alcohol  and  ether,  but  distilled  water  con- 
verted it  into  a  soft  translucent  solid,  from  which,  after  some  time, 
hydrate  of  chloral  appeared  to  be  dissolved  out,  leaving  the  camphor 
in  crystalline  grains. 
*  Rousseau's  laudanum  is  made  by  fermenting  1  p.  opium,  3  p.  honey  and  15 
p.  water,  with  some  yeast,  expressing,  filtering  and  evaporating  to  3  p.,  after 
which  1  p.  alcohol  is  to  be  added. — Paris  Codex. 
