The crowning honour of Davy's life now awaited him. His friend Sir Joseph Banks—himself the successor of such men as Sir Christopher Wren, Sir Hans Sloane, and Sir Isaac Newton—who had held the post of President of the Royal Society for forty-two years, died on 19th June, 1820, and Sir Humphry was, almost unanimously, elected on the 30th of the following November. He continued to fill the post for seven successive years, and his annual addresses are very characteristic specimens of his eloquence and suavity. He retained the old practice of delivering his speeches in full court dress,[114] and with the Society's mace (Oliver Cromwell's celebrated 'bauble') laid before him. He also continued his predecessor's practice of having weekly evening gatherings of the most distinguished men of science of the day, so long as he remained in Lower Grosvenor Street; but they were discontinued on his moving, in 1825, to 26, Park Street, Grosvenor Square.
Davy now began to find that
'Uneasy lies the head that wears a crown.'
He was worried by the numerous small duties which pertained to his prominent position, and was sadly disappointed at not being able to prevail upon the Government of the day to take up his somewhat magnificent views as to the development of the Royal Society, and the subordination of certain other great public establishments to it. He used to complain that the Government were only too glad to get anything they could out of the Society, but were loth to give back anything in return. I gather too, from what Dr. Davy says, that symptoms of failing health began, even thus early, to show themselves. He somewhat relaxed the severity of his labours—made trips to Ireland, Wales, and Scotland (dining at Edinburgh with Sir Walter Scott), chiefly with a view to enjoying the fine scenery, and the fishing and shooting; but, as regards Wales, also with the object of devising means for remedying the results produced by the noxious copper effluvia from the Smelting Works at Swansea.
In the autumn of 1821 he paid a visit to Penzance; always fond—as indeed most Cornishmen seem to be—of embracing an opportunity of revisiting his native place. On this occasion he was entertained at a public dinner; and he left his old home, doubtless expecting to see it again and again: but this was destined to be his last visit.
From 1823 to 1826 may be described as the last period of his scientific labours; and it was in a great measure devoted to investigations, undertaken at the request of the Government, into the best mode of preventing the destruction of the copper-sheathing of vessels by the action of the sea. This Davy to some extent accomplished by coating the copper with tin; but, unfortunately, the tin did not prevent (as the copper did) the fouling of the metal by accretions of seaweeds and shells; and the practical result was nil.
He was much disappointed at this, having taken great pains in the matter, and having even made a voyage to the North Sea for the purpose of conducting his experiments. Of this excursion, which included visits to Norway, Sweden, and Denmark, he has left copious records—though, as a general rule, he had now discontinued his diary—and these include his reflexions not only on the scenery, etc., through which he passed, but, according to his custom, his impressions of the distinguished men of science and others with whom he came in contact. Those circumstances which impressed Davy most deeply he often recorded, as was his practice throughout his life, in verse. A specimen may be given here in the following fragment written at Ullswater, which he visited in August, 1825:
'Ye lovely hills that rise in majesty
Amidst the ruddy light of setting suns,
Your tops are bright with radiance, while below
The wave is dark and gloomy, and the vale
Hid in obscurest mist. Such is the life
Of Man: this vale of earth and waters dark
And gloomy—but the mountains range above!
The sky—the heavens are bright!——'