Madam Galvani observed convulsions in a dead frog, which laid near an electrical machine which was in action. Although there is a diversity of information as to whether it was she or a student who noticed the incident first. As she is said to have been an invalid, and the frogs were for her benefit, it is more than likely she had an eye on them, and it would not be strange if they both saw the convulsions at the same time. However, the subject was investigated by Dr. Galvani, who was a Professor of Anatomy, and they found that. a knife touched the frog, and that when a metallic substance in contact with a nerve of the creature, was brought within the action of the electrical machine, there followed a twitching of the limb. And since that time a great many discoveries have been made about all this, and a machine constructed, called the Galvanic Battery; the principle of it, being that when two metals are connected by some substance capable of exciting their different electricities, similar effects to these described may be observed. Charges from the battery will occasion contortions and violent jerkings in dead corpses, which are rather horrible to witness. After the skin has been removed from the hind legs of frogs and some salt sprinkled over them, (while they are raw of course), the legs will quiver and jerk in a curious manner, occasioned by the action of the salt upon them. It is likely that Madam Galvani was going to have the frogs for her dinner. They have a taste between fish and chicken; you broil them over the fire, and then put a little sprinkle of salt, and the least dust of pepper, if any at all, then you will have delicious morsels. It is not necessary to cook them out of doors; building fires is a dangerous employment for children, and if you ever have any, bring them into the kitchen, and do the cooking there, where you can get help if you should need it. A word more about that pepper. Pepper, spice and other irritants, should be used with caution, if used at all, for the effect of them is to excite the coating of the stomach, and lead eventually to disease. In concluding about the battery alluded to, it is capable of producing great quantities of electricity; there is a positive pole and a negative pole,—the positive pole attracts a negative pole, and a negative pole attracts a positive pole. These terms, positive and negative, express different quantities of the fluid, positive being more, and the negative less. The term pole, in this connection, meaning point; point of concentration. Exactly how the metals are arranged in a pile, and the vessels with acid and water, and so on, are adjusted, is explained in works on the subject. We have learned so much of the ways of electricity, that we cannot be surprised as our predecessors were, even if dead bodies jerk and thump around. They have, by tracing remarkable phenomena, which astonished them, elucidated them and placed them where they belong, under and within this property of matter.
from Properties And Powers In Every-Day Matters by A Corey (1876), as noted in Odd Books : A Safe House For Literary Misfits, which is highly recommended.