102 
ON THE SYRUP OP IODIDE OF IRON. 
be boiled over a gas flame, or in any other more convenient 
way, till its brown colour has disappeared, which is easily 
known by the froth becoming white. Let the liquid be 
now at once filtered through a small filter into a bottle, 
which has previously been marked by pasting on the out- 
side of the bottle a small slip of paper at the level of 
eighteen fluid ounces, and containing thirteen ounces and a 
half of refined sugar, broken down into pieces about the 
size of peas. When the solution has all passed through, 
which fortunately takes place with unusual rapidity, let the 
filter be washed with boiling water, a further quantity of 
which must also be poured into the bottle till the liquid 
reaches the level of the mark. Let the bottle then be in 
troduced into a hot-water bath and briskly shaken at short 
intervals, till the sugar is quite dissolved ; and having 
adjusted the level of the syrup to the mark by the addition 
of water, after again shaking the bottle, let the syrup, with- 
out a moment's delay, be bottled into small phials, and se- 
cured as much as possible from contact with the air and 
light, by careful corking, and covering the bottles with 
some dark-coloured paper. These are the proportions adopt- 
ed in the Edinburgh Pharmacopoeia, and the syrup contains 
one grain of the iodide in twelve minims, or five grains in 
one drachm ; but as the syrup first proposed by Dr. A. T. 
Thomson is weaker by two-fifths, containing three grains 
to the drachm, and which we believe is the strength of the 
syrup used in England, it is evident that the proportions 
must be varied accordingly. They will therefore stand 
thus :— 
252 grains iodine 
100 grains iron filings 
2£ oz. cold water 
10 oz. pure sugar. 
Let the syrup, when finished, measure twelve ounces 
and a half, the level occupied by this quantity having been 
marked off on the bottle before-hand. It is advisable that 
