Tesla's engine

From the diary "Moji izumi" (My inventions) by Nikola Tesla published by the Museum of Nikola Tesla

In 1899, when I was forty years old and carrying on my experiments in Colorado, I could hear thunderclaps very distinctly at a distance of 550 miles. The limit of audition for my young assistants was scarcely more than 150 miles. Thus my ear was over thirteen times more sensitive. Yet at that time I was, so to speak, deaf in comparison with the acuteness of my hearing while under the nervous strain. In Budapest I could hear the ticking of a clock which was in the third room adjacent to mine. A fly alighting on a table in the room would cause a dull thud in my ear. A carriage passing at a distance of a few miles fairly shook my whole body. The whistle of a locomotive twenty or thirty miles away made the bench or chair on which I sat vibrate so strongly that the pain was unbearable. The ground under my feet trembled continuously. I had to support my bed on rubber cushions to get at least a little rest. The roaring noises from near and far often produced the effect of spoken words which frightened me to the point of not being able to divide them according to their accidental components. The sun rays, when periodically intercepted, caused an earthquake in my brain that stunned me. I had to collect all my will power to pass under a bridge or other structure as I experienced a crushing pressure on the skull. In the dark I had the sense of a bat and could detect the presence of an object at a distance of twelve feet by a peculiar creepy sensation on the forehead. My pulse varied from a few to two hundred and sixty beats and all the tissues of the body suffered from cramps and tremors which were perhaps the hardest to bear.

A well-known physician who gave me daily large doses of Potassium Bromide pronounced my disease unique and incurable. It is my eternal regret that I was not under the observation of experts in physiology and psychology at that time. I clung desperately to life, but never expected to recover. Can anyone believe that a person in such hopeless conditions could ever be transformed into a man of astonishing strength and tenacity, able to work thirty-eight years almost without a day's interruption, and be still strong and fresh in body and mind? It is my case. A powerful desire to live and to continue the work, and the assistance of a devoted friend and athlete accomplished the wonder. My health returned and with it the vigor of mind. In attacking the problem again I almost regretted that the struggle was soon to end. I had so much energy to spare. When I undertook the task it was not with a resolve such as men often make. With me it was a sacred vow, a question of life and death. I knew that I would perish if I failed.

Now I felt that the battle was won. Somewhere in the depth of the brain there was the solution, but I could not find a way to express it. One afternoon, which I will always remember, I was enjoying a walk with my friend in the City Park and reciting poetry. At that age I knew entire books by heart, word for word. One of these texts was Goethe's "Faust." The sun was setting and reminded me of the famous passage…

As I uttered these inspiring words the idea came like a flash of lightning and in an instant the truth was revealed. I drew with a stick on the sand the diagrams shown six years later in my address before the American Institute of Electrical Engineers, and my companion understood them perfectly. The images I saw were wonderfully sharp and clear and had the solidity of metal and stone, and they were so clear that finally I told my friend: "Look at my engine; look how it can be in the opposite direction." I cannot describe my emotions. Pygmalion seeing his statue come to life could not have been more moved. A thousand secrets of nature which I might have stumbled upon accidentally I would have given for that one which I had wrested from it against all odds and at the peril of my existence.