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XLIII. Process for obtaining Iode. By Mr, ALEXANDER 
GARDEN. 
Old Compton Street, Soho, March 21, 1814. 
Sins, — 1 ue following method, which I have lately employed 
for procuring iode, I take the liberty of communicating for inser- 
tion in the Philosophical Magazine, (should you deem it of suffi- 
cient importance,) and which, in addition to the information al- 
ready therein contained on the same subject may not be altoge- 
ther unacceptable to some of your chemical readers. It is as 
follows : 
1. To a concentrated watery solution of kelp (or the waste ley 
of the soap-maker where kelp has been employed) from which 
the greater part of the crystallizable salts have been separated by 
the usual processes of evaporation and crystallization, add red 
oxide of lead in the proportion of one ounce to about a pint of 
the former; boil the mixture over a slow fire to dryness, and in- 
crease the heat towards the end of the solution so as to carbonize 
any animal or vegetable matter which the substance may contain. 
This last may most conveniently be performed in an iron ladle. 
2. Digest the dried mass in a quantity of cold water sufli- 
cient to extract the greatest portion of the soluble matter, filter, 
and evaperate the clear liquid to the consistence of a syrup. 
3. Introduce the liquid obtained in the last process, together 
with the saline matter which may have separated during the eva- 
poration, into a glass mattrass, and pour thereon about twice its 
_bulk of alcohol; digest with a gentle heat for a few minutes and 
then suffer the vessel with its contents to grow cold. 
4, Decant the clear alcoholic solution into a tubulated retort, 
adapt a receiver, and by means of a gentle and gradually applied 
heat distil off the alcohol. The saline matter which remains in 
the retort is to be washed out and evaporated to dryness in a 
capsule of Wedgwood’s ware. 
5. Intreduce the dry salt thus obtained into a mattrass with a 
short neck, to which a glass tube about six or eight inches long, 
and sufficiently large to fit over the external diameter of the neck, 
has been luted, and pour over the salt by means of a long- 
necked funnel twice its weight of strong sulphuric acid. Heat 
the mixture gradually by a spirit or Argand’s lamp, and the iode 
will immediately begin to rise in the form of a dense and beau- 
tiful violet-coloured gas, which will be condensed in the upper 
part of the vessel in black shining crystals; when the gas ceases 
to be disengaged the mattrass should be allowed to cool: the 
iode may then be washed out with water, dried on white filtering 
paper at a temperature not exceeding 100° of Fahrenheit, and 
inclosed in a bottle accurately fitted with a glass stopper. 
The chief advautage of the preceding processes is to separate 
Vol. 43. No. 191. March 1814, pretty 
