Commentary on the Effect of Electricity on Muscular Motion

...flashing with lightning, but even with a shimmering sky original: "coruscante cælo"; likely referring to "heat lightning" or distant flashes without thunder. But at those times, no contractions were ever observed, perhaps because either shimmers of this kind do not depend on electricity, or if they do, they happen in a too distant place or by a far different cause than lightning usually does. But let the Physicists original: "Physici"; in the 18th century, this referred to natural philosophers or scientists studying the physical world especially see to these matters.

PART THREE

On the powers of animal electricity in muscular motion.

Having tested the powers of stormy atmospheric electricity, my mind burned with the desire to also experience the power of daily and calm electricity.

For this reason, when I had occasionally seen prepared frogs placed on iron railings original: "ferreis cancellis", which surrounded a certain hanging garden a terrace garden common in Italian villas of the period of our house, equipped also with brass hooks in the spinal cord, fall into their usual contractions—not only with a lightning-filled sky, but sometimes even when it was quiet and clear—I thought those contractions took their origin from changes which happen during the day in atmospheric electricity.

Hence, not without hope, I began to diligently investigate the effects of these changes in these muscular movements and to test them by various methods. Therefore, at different hours, and that for many days, I inspected the animals appropriately prepared for the task; but there was scarcely any motion in their muscles. Wearied at last by vain expectation, I began to press and squeeze the brass hooks, by which the spinal cords were pierced, against the iron railings, to see if by this kind of maneuver muscular contractions might be excited, and whether they might show any variety and change according to the various state of the atmosphere and electricity; indeed, I observed contractions not rarely, but with no regard for the varied state of the atmosphere and electricity.

However, since I had only observed these contractions in the open air (for I had not yet tested the matter in other places), I was almost convinced that such contractions resulted from atmospheric electricity having crept into the animal, accumulated within it, and rapidly exiting from it upon the contact of the hook with the iron railings; for it is easy...