These papers, together with one on a New Phenomenon of Electro-Magnetism, published in 1823, are interesting in relation to the development of Oersted’s great discovery, and in connection with the subsequent work of Faraday.
With that power of generalisation which is one of the distinguishing marks of his genius, he shows the possible connection of the facts he had observed with the phenomena of terrestrial magnetism. He concludes his first paper by asking
“whether the magnetism of the earth may not be owing to its electricity, and the variation of the needle to the alterations in the electrical currents of the earth, in consequence of its motions, internal changes, or its relations to solar heat; and whether the luminous effects of the auroras at the poles are not shown, by these new facts, to depend on electricity. This is evident, that if strong electrical currents be supposed to follow the apparent course of the sun, the magnetism of the earth ought to be such as it is found to be.”
It is perhaps idle to speculate on such a matter, but it is more than likely that had Davy been free from the cares and restraints of office, and from the innumerable distractions inseparable from his position in the social and scientific world of London, he might have revealed the possibilities in electro-magnetism with the same brilliant success as he had done those of voltaic electricity. He was now at the maturity of his mental power, and had still much of the enthusiasm and ardour which characterised his earliest work, and under serener conditions he might have achieved triumphs not less striking than those reserved for Faraday. His few short papers on the subject indicate that he fully realised the great wealth of the new territory thus opened out to science, and into which he was one of the first to penetrate. But it is sad to think that he might have extended a more generous hand to one who, equally with himself, was striving to enter the new land, and who eventually did enter and for a time possessed it. In the concluding words of Davy’s last paper on electro-magnetism, we discern in the allusion to Wollaston’s idea of the possibility of the rotation of the electro-magnetic wire round its axis “the rift within the lute” in his relations towards his assistant, which widened in the matter of the condensation of chlorine, and which threatened to become an open breach when Faraday was elected into the Royal Society.
The jealousy thus manifested by Davy is one of the most pitiful facts in his history. It was a sign of that moral weakness which was at the bottom of much of his unpopularity, and which revealed itself in various ways as his physical strength decayed.
Greedy as he was of fame—that infirmity of noble minds—many incidents in his life up to this period prove that he was not wanting on occasion in a generous appreciation of the work of his contemporaries, even in fields he might reasonably claim as his own. But, although in his intellectual combats he could show at times a certain knightly courtesy, it must be confessed that he was lacking in the magnanimity which springs from the charity that envieth not.
In genius he was unquestionably superior to Faraday; in true nobility of character he was far below him. It is almost impossible to avoid comparing him with Faraday. Indeed it is one of the penalties of his position that he has to be tried by so severe a standard, and it may well be that his good name, which, as Bacon says, is the proper inheritance of the deceased, has suffered unduly in consequence. His true place in the history of science is defined by his discoveries; it is a sad reflection that the lustre of his fame has been dimmed rather than heightened by what has been styled the greatest of them all—Faraday. But there has undoubtedly been injustice in the comparisons which have been made. What Davy was to Faraday, Faraday would have been the first to admit. Davy made himself what he was by the sheer force of his unaided genius; what Faraday became was in large measure due to his connection with Davy, and the germs of his greatest works are to be traced to this association. This fact has been frankly acknowledged by Faraday. To the end of his days he regarded Davy as his true master, preserving to the last, in spite of his knowledge of the moral frailties of Davy’s nature, the respect and even reverence which is to be seen in his early lecture notes and in his letters to his friend Abbott. Faraday was not easily roused to anger, but nothing so effectually moved him as any aspersion of Davy’s character as a man of science, or any insinuation of ungenerous treatment of himself by Davy.
At about this time—that is, in the autumn of 1823—Davy gave the first signs of the obscure malady which ultimately occasioned his death. In a letter to his brother, in which he describes his symptoms, we have a reference, also, to his domestic worries: “To add to my annoyances, I find my house, as usual, after the arrangements made by the mistress of it, without female servants; but in this world we have to suffer and bear, and from Socrates down to humble mortals, domestic discomfort seems a sort of philosophical fate.”
He was able, however, to continue his scientific work, but instead of the fame and applause on which he so confidently counted, he found only disappointment and chagrin.
In 1823 the Admiralty sought the advice of the Royal Society as to “the best means of securing to the service copper of the most durable quality, and such as will preserve the smoothest surface.” A committee of the Society was appointed, under Davy’s direction, to consider the question, which ultimately resolved itself into one of preventing the corrosion of the metal. In this matter Davy’s special experience proved most useful, and, as a fact, he took all the experimental part of the inquiry upon himself, and with what result may be seen from the following letter to his brother:—