^o6 SirH. Davy's further Experiments 
5. I have examined three specimens of alkali formed by the 
combustion of vegetables that grow on the sea shore, one from 
Sicily, one from Spain, and the third from the Roman states, 
but not one of them afforded any indications of the presence 
of iodine. 
6. I evaporated a considerable quantity of sea water pro- 
cured at Sestri of Levanto in Liguria, in a part of the bay 
remote from any source of fresh water ; but I could gain no 
unequivocal evidences of the presence of the compounds of 
iodine in it. The residual liquor after the common salt had 
been separated, did not act upon silver nor colour sulphuric 
acid. The first crystals of salt which fell down when fused 
upon silver, appeared to me to tarnish it more than the last ; 
from which it appeared probable that they may have contained 
some triple compound of iodine, yet after being ignited, they 
did not colour sulphuric acid. When a large quantity of this 
water was electrised by a Voltaic apparatus, and the products 
separated at the positive pole collected in a small cup of gold, 
which was covered with cement, except in the interior and 
lower part forming the circuit, a yellow solution was obtained, 
which, when it was exposed to the negative pole of a Voltaic 
apparatus, yielded a black powder fixed in the fire, and not 
unlike the compound formed by heating gold and iodine 
together ; but the quantity was too minute to admit of analysis, 
and a dark coloured substance is likewise obtained by nega- 
tively electrifying oxy muriate of gold, and there can be no 
doubt but that this substance formed a principal part of the 
solution.* 
* Iodine, like chlorine, I find combines both with gold and platinum, when heated 
with them, or when they are exposed to them in its nascent state. 
