Galvani, professor of anatomy at the University of Bologna, was studying the nervous system of the frog when he noted that distant electrical discharges would cause violent muscular contractions in a dissected frog if the lumbar nerve was in contact with a metal instrument. He called this force "animal electricity" but it quickly became known across Europe as "galvanism."

Galvani was in error-the phenomena he observed was caused by the generation of electricity by different metals in a moist atmosphere-but his mistake had manifold consequences. The idea of galvanism forms the background to Mary Shelley's Frankenstein, while the physicist Alessandro Volta, in disproving Galvani's theory, was led to the invention of the electric battery.

Galvani first published his findings in the proceedings of the Bologna Academy and Institute of Sciences and Arts in March 1791. A very small edition of the paper was then printed to be distributed to Galvani's friends. Though the Health Sciences Library owns one of that rare edition, the copy on display here was part of a printing later that same year designated for public sale. The plate shows Galvani's laboratory with the dissected frog's legs, an electrostatic machine (left), and a Leyden jar (right).