Since his last communication to the Society, the author has made a variety of experiments, with the view of farther testing the truth of the proposed law which limits the direct action of the voltaic current to the solvent, in solutions of primary elementary combinations in the more important solvents. All his researches have farther confirmed this law in regard to aqueous solutions. Amongst those which he has examined is an aqueous solution of iodic acid as a type of oxyacids; and he found that by connecting such a solution mixed with starch, with a solution of starch in water, by means of asbestus, no iodine was indicated when the starch solution was negative, but was immediately manifested when the iodic solution was negative from the reducing action of hydrogen. In the whole circumstances, he has no hesitation in concluding, “that when aqueous solutions of primary combinations of elementary bodies are submitted to voltaic agency, the dissolved substance is not directly decomposed by the current, but only the solvent.”