ON  CHLORIMETRY. 
61 
little  water  or  some  fatty  body.  It  is  kept  in  a  narrow  vial 
(mkhalel)  made  of  some  of  the  precious  metals.  When  it  is  to 
be  applied,  a  very  fine  stylet  (mirowed,)  highly  polished,  is  dipped 
into  the  bottle,  and  this  covered  with  koheul,  is  passed  between 
the  eyebrows  previously  closed.  The  edges  of  the  lids  acquire  a 
very  deep  tinge,  which  is  blueish,  if  there  is  nothing  used  but 
antimon}^,  but  black,  if  the  sulphuret  has  been  mixed  with  lamp- 
black. The  blue  color  is  found  amongst  the  negroes,  who  never 
use  the  latter  ingredient. 
In  those  tribes  where  the  antimony  is  difficult  to  obtain,  koheul 
is  composed  of  the  charcoal  of  the  laurel,  rose  and  black  pepper* 
very  finely  pulverized.  At  other  times,  to  give  more  astringent 
power  to  the  preparation,  they  mix  in  a  mortar,  in  equal  propor- 
tions, sulphuret  of  antimony,  sulphate  of  copper,  burnt  alum, 
carbonate  of  copper,  some  cloves  and  a  little  lampblack.  This 
is  carefully  mixed  together.  Prostitutes  make  their  koheul  with 
a  powder  of  the  dried  saffron  leaves,  mixed  with  lemon  juice. 
This  preparation  must  be  applied  for  many  hours,  but  will  last  a 
long  time.  Frequently  the  sweet  rush  {andro  pegon  nardus,) 
and  benzoin,  is  mixed  with  koheul  to  improve  the  power  of  vision, 
and  from  the  use  of  this  substance  in  all  forms  of  opthalmitic,  I 
have  found  the  greatest  success. —  Virg.  Med.  and  Surg.  Jour., 
from  "  Medicine  and  Hygiene  among  the  Arabs." 
ON  CHLORIMETRY. 
Br  C.  Ncellner. 
The  general  employment  of  chloride  of  lime  as  a  bleaching 
and  oxidizing  agent,  with  its  readiness  to  undergo  change  when 
long  kept,  and  the  variableness  of  its  chemical  composition  even 
when  apparently  prepared  in  a  similar  manner,  has  given  rise  to 
a  number  of  methods  for  determining  its  practical  value. 
Chemical  manuals  contain  numerous  methods  for  this  purpose, 
generally  founded  on  volumetric  principles ;  Bulbs  alone,  in  his 
<  Theory  and  Practice  of  Pharmaceutical  Experimental  Chemis- 
try,' proposes,  by  means  of  sulplmrous  acid,  to  form  a  quantity 
of  sulphuric  acid  corresponding  with  the  efficient  amount  of 
chlorine  as  a  bleaching  or  oxidizing  agent,  and  thus  to  determine 
it  as  sulphate  of  baryta  by  weighing. 
