“Firle, Jany 30, 1824.
“I have lately made a discovery of which you will for many reasons be glad. I have found a complete method of preserving the copper sheeting of ships, which now readily corrodes. It is by rendering it negatively electrical. My results are of the most beautiful and unequivocal kind: a mass of tin renders a surface of copper 200 or 300 times its own size sufficiently electrical to have no action on sea water.
“I was led to this discovery by principle, as you will easily imagine; and the saving to government and the country by it will be immense. I am going to apply it immediately to the navy. I might have made an immense fortune by a patent for this discovery, but I have given it to my country; for in everything connected with interest, I am resolved to live and die at least ‘sans tâche.’”
His method of rendering the copper negatively electric consisted in affixing to the sheets a number of short bars of iron or zinc, properly curved to the shape of the vessel. In this way the “protectors,” as the zinc or iron bars were called, gradually corroded, whilst the copper remained unattacked. But, as Dr. Paris remarks, the truth of the theory was completely established by the failure of the remedy. The ship’s bottom became so foul by the adhesion of shells and weed that her speed was greatly impeded, and after a number of trials, in the course of which a steam vessel was placed at his disposal, in which he made a voyage to Norway and back, the Admiralty directed the protectors to be removed. To add to his mortification, the order was issued immediately after a communication to the Royal Society announcing the complete success of his plan. Throughout the whole of this business he was exposed to a number of vexatious attacks, which greatly embittered him and reacted disastrously upon his health and character. So long as there was the hope of success and the prospect of reward his claims to the originality of the invention were contested: no sooner was the project abandoned than he was assailed in the periodical press and made an object of sarcasm and censure. As might be imagined, his philosophy was not proof against such attacks. He wrote to his friend Children—
“A mind of much sensibility might be disgusted, and one might be induced to say why should I labour for public objects, merely to meet abuse?—I am irritated by them more than I ought to be; but I am getting wiser every day—recollecting Galileo, and the times when philosophers and public benefactors were burnt for their services.”
During the autumn his indisposition increased, and his home letters show that the wonderful elasticity of spirit, which, as his brother remarks, had hitherto carried him lightly and joyously through life, over all its rubs and cares, now seemed to flag. He had an ailing winter, and with the spring came news of his mother’s illness. He could only write with difficulty:—“If it please God, I will certainly be at Penzance the last week in October or the first in November.” He never saw her again; she rallied for a time, but died somewhat suddenly in September. Davy never really recovered from the shock of her death. It was with the greatest difficulty that he was able to preside at the anniversary meeting of the Society on the ensuing St. Andrew’s Day. The effort was so marked that those near him feared he was on the verge of apoplexy, and he was too ill to attend the dinner. A few weeks later he had a slight attack of paralysis, from which he only slowly recovered. His good friend Dr. Babington[J] ordered him abroad, away from “the convivial epicurean habits of London society,” and from “the many annoyances and causes of injurious excitement to which he was exposed at home.” He set out with his brother John, in the depth of winter—“a dreary beginning of a dreary journey.” He avoided Paris; he would not even pass through it, so apprehensive was he that he should not escape from “the allurement—or, rather, excitement—of its society” if he stopped there. The roads were in a wretched state, the country covered with snow, and “no object to arrest the eye, except a village here and there rising out of the white waste, or a distant steeple, or some solitary tree.” The cold was intense, and once or twice the travellers were benighted, the wheels of their carriage being locked in the frozen ruts. As they passed through the towns Davy, who seemed to cling to life with a passionate tenacity, would visit the churches, and, falling on his knees, would offer up a silent prayer. They crossed Mont Cenis in a storm of wind and amidst drifting snow, and with great difficulty got down to Susa on sledges. The snow in Lombardy was deeper than in the passes of the Alps, and even at Ravenna, where they arrived in the first week of March, it was still to be seen in the ditches. Here his brother left him, his duties as an army surgeon calling him to Corfu. In spite of severe weather, the discomforts of travelling at such a time, and the forced delays at wretched inns, Davy gradually improved; his brother noted before he left that he was certainly stronger, less paralytic, and more active. He wrote to his friend Poole:—
[J] “Babington, the best and warmest-hearted friend, the kindest husband and father, and perhaps the most disinterested physician of his time; with good talents, and a fine tact, and a benevolence which created sympathy for him wherever he appeared, and I believe often cured his patients.”
“I am, thank God, better, but still very weak, and wholly unfit for any kind of business and study. I have, however, considerably recovered the use of all the limbs that were affected; and as my amendment has been slow and gradual, I hope in time it may be complete. But I am leading the life of an anchorite, obliged to abstain from flesh, wine, business, study, experiments, and all things that I love; but this discipline is salutary, and for the sake of being able to do something more for science, and I hope for humanity, I submit to it, believing that the Great Source of intellectual being so wills it for good.”
He tells Poole that he had chosen Ravenna—this spot of the declining Empire of Rome—as one of solitude and repose, and as out of the way of travellers and in a good climate. He was interested, too, in its many associations with his friend Byron, with Dante, and in its old-world memories of Theodoric and his lost legions. How the place affected him in his state of physical enfeeblement, but with his mind chastened and purified, may be seen in the character of much that he wrote there, and particularly in his poems, with their many notes of sadness and hope, trust and resignation. He was lodged in the Apostolical Palace by the kindness of the Vice-Legate—a graceful, learned, and accomplished man, with whom he contracted a warm friendship. He says he could not speak of his goodness without tears of gratitude in his eyes, and with this exception and an occasional visit from the Countess Guiccioli he had no society. Most of his time was spent in riding amidst the pines and junipers, or following the petzardone among the marshes of La Classe; or in reading and in the study of natural history.
“The natural strength of his mind,” says his brother, “was very clearly manifested under these circumstances. Dependent entirely on his own resources; no friend to converse with; no one with him to rely on for aid, and in a foreign country, without even a medical adviser; destitute of all the amusements of society; without any of the comforts of home—month after month, he kept on his course, wandering from river to river, from one mountain lake and valley to another, in search of favourable climate; amusing himself with his gun and rod, when sufficiently strong to use them, with ‘speranza’ for his rallying word.”
With the approach of spring he passed by way of Gorizia into Illyria, and, as the heat increased, into Upper Austria, Bavaria, and Switzerland, and back, in the late summer, to Illyria. His journals give a fairly full account of his movements and of the manner in which he spent his time; they also indicate his state of mind, the alternations of hope and despondency, and his constant struggles with the insidious disease which was gradually exhausting his physical powers.
He wrote to his wife from Laybach:—