The author commences his paper with a description of two forms of Electric Batteries, which he used in his experiments, and which consisted of bars of antimony and bismuth. One of these, which was chiefly intended for currents excited by solar and astral influences, was so delicate as to make the needle of the galvanometer deflect at right angles, when one end of the battery was exposed to the influence of clear summer's sun; and he therefore considers it a very delicate meteorological instrument. The other form of battery was principally used for thermo-electric currents, from a low flame of gas, or a spirit-lamp.