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Page:Popular Science Monthly Volume 83.djvu/615

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THE HISTORY OF OHM'S LAW
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experiment. This is a serious mistake on the part of Ohm and it is hard to see just why ho did himself this injustice. He may have assumed that the scientific public was familiar with all of his printed papers—an unsafe assumption at any time—and that direct reference to them was unnecessary. Ohm's book was only made possible by his experimental work and everything of value in it is the direct outcome of the laboratory, yet in the book Ohm writes as if the results reached were deductive and based on the three hypotheses cited above. In this Ohm laid the ground for the misunderstanding of his work by his contemporaries, who did not realize that its basis was experimental and therefore subject only to experimental proof or disproof.

Perhaps Ohm thought that the rather meager foundation of experimental data would be regarded as inadequate for the superstructure, or it may be that he really felt that the experiments had led him to the knowledge of the fundamental causes of the phenomena of conduction, and that his theory was more secure by being logically developed from these supposed fundamental truths. In either event he retarded rather than helped his cause. A third reason that might be assigned would be his desire, supposing him to have it, to be regarded as a deductive rather than as an inductive philosopher. He had, of course, imbibed some of the modern view of the importance of experimentation, else he would not have experimented, but he very likely still retained a good deal of the old Greek notion that by a process of pure reasoning one may reach new truth. In this case experimentation is not so much a source of new knowledge as a new form of thought stimulation. From such a viewpoint the experiments of Ohm had indeed served their purpose so soon as they were completed and he was quite right in ignoring them. Such a view of Ohm's position is strengthened by the fact that he seems to have taken no pains to remove the impression, universal in his day and which persists somewhat even to the present, that his laws were based on theory only and had no experimental origin or support.

So far then as Ohm is concerned we must conclude that however much he may have valued his experimental work for himself, he was well content that the public should consider his laws as being of theoretic and not of experimental origin.

The view which the scientific public early reached as to the value of Ohm's work is well expressed in the following paragraph taken from Cajori's "History of Physics" (pp. 230-1):

The following year Ohm published a book entitled "Die Galvanische Kette, mathematisch bearbeitet. "It contained a theoretic deduction of Ohm's law, and became far more widely known than his article of 1826, giving his experimental deduction. In fact, his experimental paper was so little known that the impression long prevailed and still exists that he based his law on theory and never established it empirically. This misapprehension accounts, perhaps, for the