The attractions of society and his early death (he was only fifty) stopped his work on agricultural chemistry; and it was not until 1840, eleven years after Davy's death, that Liebig published his ever famous work on the same subject.
Rumford and Davy proved that heat was not matter, as had been previously supposed, but a form of energy—the vis viva of the molecules. But the crowning discoveries of Davy were those necessitating the use of the electric battery. To Davy, "the electrolysis of every chemical compound was a new application of the great law established by Newton: 'to every action there is an equal and opposite reaction." By means of the electric battery he decomposed bodies which were generally regarded as elements or simple bodies.
On 19th October 1807 Davy isolated the metals potassium and sodium by electrolyzing potash and soda. In the former case, potassium and hydrogen were evolved at the negative pole, and oxygen at the positive pole of the battery. When Davy first saw the metallic globules of potassium, "he could not contain his joy—he actually bounded about the room in ecstatic delight; and some little time was required for him to compose himself sufficiently to continue the experiment." This was the
