Commentary on the Effect of Electricity on Muscular Motion

Struck by the novelty of the event, we began to test and explore the matter in various ways, yet using the same scalpel, so that we might uncover the causes of this unexpected difference, if possible. This new labor did not prove to be in vain; for we discovered that the entire phenomenon was to be attributed to the specific part of the scalpel that we held with our fingers. We found that if the scalpel had a bone handle original: "osseum manubrium", no movements occurred when a spark was drawn while that handle was gripped by the hand. However, the movements did appear if the fingers were placed either on the metal blade itself or on the iron rivets original: "ferreis clavulis" that secured the blade to the handle.

Therefore, since dry bones possess an insulating idioelectric: a substance that can be electrified by friction but does not easily conduct electricity; an insulator. nature, while the metal blade and iron rivets possess a conducting anelectric: a substance that does not become electrified by friction but conducts electricity well; a conductor. nature, we came to the suspicion that perhaps it happened that when we held the bone handle with our fingers, all access was blocked to the electric fluid original: "electrico fluido". In the 18th century, electricity was thought to be a weightless fluid that flowed through bodies. acting upon the frog by whatever means, but access was granted when we gripped the blade or the rivets connected to it.

To place this matter beyond all doubt, we used a thin cylinder instead of a scalpel. At one time we used a glass cylinder (H, Figure 2) which had been thoroughly polished to remove all moisture and dust, and at another time an iron cylinder (G). With the glass cylinder, we did not merely touch but actually rubbed the crural nerves The nerves of the thigh. at the moment a spark was drawn; yet, despite all our persistent efforts, the phenomenon never occurred, even though countless and more powerful sparks were forced from the machine's conductor at a very short distance from the animal. However, the phenomenon did occur if the iron cylinder was even lightly applied to those same nerves and only tiny sparks were drawn.

From this, it became clearly established to us that what we had suspected was true: that contact of a conducting body original: "deferentis corporis" with the nerves is required for the phenomenon to happen. But since both the object touching the nerves and the human being touching that object were involved, we placed the iron cylinder G upon the nerves without holding it in our hands, to determine whether the phenomenon should be attributed to the person and the iron cylinder together, or to the cylinder alone. With things arranged in this way, no movement of the muscles occurred when a spark was drawn. Therefore, in place of the cylinder, we used a very long wire (K K, Figure 2) to see if it might in some way compensate for the absence of the human, or not; and behold! the muscle contractions returned once more at the discharge of a spark.