Many have signalized themselves by melting their estates in crucibles. I was born to no fortune, and therefore had only my mind and body to devote to knowledge, and the gratitude of posterity will attest, that neither mind nor body have been spared. I have sat whole weeks without sleep by the side of an athanor, to watch the moment of projection; I have made the first experiment in nineteen diving engines of new construction; I have fallen eleven times speechless under the shock of electricity; I have twice dislocated my limbs, and once fractured my skull, in essaying to fly[c]; and four times endangered my life by submitting to the transfusion of blood. [c] In the sixth chapter of Rasselas we have an excellent story of an experimentalist in the art of flying. Dr. Johnson sketched perhaps from life, for we are informed that he once lodged in the same house with a man who broke his legs in the daring attempt. In the first period of my studies, I exerted the powers of my body more than those of my mind, and was not without hopes that fame might be purchased by a few broken bones without the toil of thinking; but having been shattered by some violent experiments, and constrained to confine myself to my books, I passed six and thirty years in searching the treasures of ancient wisdom, but am at last amply recompensed for all my perseverance. The curiosity of the present race of philosophers, having been long exercised upon electricity, has been lately transformed to magnetism; the qualities of the loadstone have been investigated, if not with much advantage, yet with great applause; and as the highest praise of art is to imitate nature, I hope no man will think the makers of artificial magnets celebrated or reverenced above their deserts. I have for some time employed myself in the same practice, but with deeper knowledge and more extensive views. While my contemporaries were touching needles and raising weights, or busying themselves with inclination and variation, I have been examining those qualities of magnetism which may be applied to the accommodation and happiness of common life. I have left to inferior understandings the care of conducting the sailor through the hazards of the ocean, and reserve to myself the more difficult and illustrious province of preserving the connubial compact from violation, and setting mankind free for ever from the danger of suppositious children, and the torment of fruitless vigilance and anxious suspicion.