He returned to Bayswater on the 30th of September, 1843, and at last consented to call in medical aid, though he was by no means aware of his dangerous state. He supposed, indeed, that the pain he felt, which was on time right side, proceeded from an affection of the liver; as both times, when he had inflammation of the lungs, the pain was on the left side. On the 2d of October I went with him to call on Mr. Lawrence, in whom he had the greatest confidence; and that gentleman told him without hesitation that his disease was in his lungs. He was evidently very much struck at this announcement, but, as he had the fullest reliance on Mr. Lawrence's judgment, he was instantly convinced that he was right; and, I think, from that moment he had no hope of his ultimate recovery, though, in compliance with the wishes of different friends, he afterwards consulted several other eminent medical man, of whom Dr. Chambers and Mr. Richardson attended him to the last.

As soon as Mr. Loudon found that his disease was likely to prove fatal, he determined, if possible, to finish the works he had in hand, and he laboured almost night and day to do so. He first, with the assistance of his draughtsman, finished a plan for Baron Rothschild; then one for Mr. Ricardo, another for Mr. Pinder, and, finally, a plan for the cemetery at Bath. He had also engaged to make some additional alterations in the grounds of Mr. Fuller at Streatham, and he went there on the 11th of October, but he was unable to go into the garden; and this was the last time he ever attempted to visit any place professionally. He continued, however, to walk in the open air in his own garden, and in the grounds of Mr. Hopgood, nurseryman, at Craven Hill, for two or three days longer, though his strength was fast decreasing; and after the 16th of October he did not leave the house, but confined himself to his bedroom and a drawing-room on the same floor. Nothing could be more awful than to watch him during the few weeks that yet remained of his life. His body was rapidly wasting away; but his mind remained in all its vigour, and he scarcely allowed himself any rest in his eagerness to complete the works that he had in hand. He was particularly anxious to finish his Self-Instruction for Young Gardeners, which is published nearly in the state he left it, though had he lived it would probably have been carried to a much greater extent. About the middle of November, the medical men who attended my poor husband pronounced his disease to have become chronic bronchitis; and this information, combined with the pressure of 'pecuniary difficulties, had a powerful effect upon him. He now made an effort that can only be estimated by those who know the natural independence of his mind, and the pain it gave him to ask even a trifling favour, he wrote a letter stating his situation, and that the sale of 350 copies of the Arboretum would free him from all his embarrassments. This letter he had lithographed, and he sent copies of it to all the nobility who took an interest in gardening. The result was most gratifying. The letter was only dated the 1st of December, and he died on the 14th of that month; and yet in that short space of time the noblemen he appealed to, with that kindness which always distinguishes the English aristocracy, purchased books to the amount of £360. Mr. London had intended to forward similar letters to all the landed proprietors and capitalists; and, though only a few were sent, they were responded to with equal kindness. Our munificent and noble-minded friend Joseph Strutt, Esq., took ten copies; and letters from two of our kindest friends ('William Spence, Esq., and Robert Chambers, Esq.), ordering copies of the Arboretum, arrived the very day be died.'