Franklin erected the first rod over his house in Philadelphia in September, 1752. It was made of iron with a sharp steel point rising seven or eight feet above the roof, the other end being sunk five feet in the ground. Franklin charged a Leyden Jar from his rod in April, 1753. Professor Richmann, of St. Petersburg, was killed by a flash from his apparatus on August 6th, 1753. BROTHER POTAMIAN. [Illustration: ALOISIO GALVANI] FOOTNOTES: [8] Scientific Writings of Joseph Henry, Vol. I., p. 201. [9] Frequently referred to as Lullin's experiment. [10] Every schoolboy knows that the electricity which passed down the kite-string was not drawn from the clouds, but was due to their inductive action on the pointed conductor attached to the kite. Kant calls Franklin the "Modern Prometheus." CHAPTER IV. GALVANI, DISCOVERER OF ANIMAL ELECTRICITY. It is a well-known fact, often commented on in the history of medicine, that Harvey, the discoverer of the circulation of the blood, did not give the details of his discovery to the public for some twenty years after he had first reached it. The reason for his delay was twofold. With the characteristic patience of a real investigator in science, Harvey wanted to work out the details of his discovery for himself before giving it to the public, and wished to be sure of all he would have to say about it before committing it to print. He had not, as had indeed none of the really great discoverers in science, that intense desire for publicity which causes smaller men to rush into print with their embryonic discoveries, or oftener, their supposed discoveries, the moment they get their first distant glimpse of a new truth or see some mirage of a distant scientific principle, perhaps already well known, in their heated imaginations. Small men squabble about priority in small discoveries, and rush headlong into print, lest some one should anticipate their wonderful observation. The example of Harvey can scarcely be commended too highly, for if followed, it would save the world of science a lot of bother and obviate the necessity of taking back many things that have been proclaimed in the name of science. Fortunately, it has been the rule among genuine students of science, not because of any deliberate imitation of their great predecessors, but because of modest assurance of the worth of their work and honest desire to perfect it before giving it to the world.