[190] On the 18th May, 1780, Watt wrote Boulton, then in London, as follows:--“I am sorry, my dear Sir, to prove in any shape refractory to what you desire, but my quiet, my peace of mind, perhaps my very existence, depend on what I have told you. I am unhappy in not having any person I can advise with on this subject; and my own knowledge of it is insufficient. Therefore, if I appear too rigid, do not blame me, but my ignorance and timidity.” And again, on the 19th, on returning the draft mortgage, he wrote:--“If my executing this deed cannot be dispensed with, I will do it, but will not execute any personal bond for the money. I would rather assign you all Cornwall on proper conditions than execute this.” [191] Watt to Boulton, 11th April, 1780. Judging by the correspondence of Watt, his sufferings of mind and body at this time must have been excessive; and the wonder is how he lived through it. But “the creaking gate hangs long on its hinges,” and he lived to the age of eighty-three, long surviving his stronger and more courageous partner. Intense headache seemed to be his normal state, and his only tolerable moments were those in which the headache was less violent than usual. His son has since described how he remembered seeing his father about this time, sitting by the fireside for hours together, with his head leaning on his elbow, suffering from most acute sick-headaches, and scarcely able to give utterance to his thoughts. “My headache,” he would write to Boulton, “keeps its week-aversary to-day.” At another time, “I am plagued with the blues; my head is too much confused to do any brain-work.” Once, when he had engaged to accompany his wife to an evening concert, he wrote, “I am quite eat up with the mulligrubs, and to complete the matter I am obliged to go to an oratorio, or serenata, or some other nonsense, to-night.” Mrs. Watt tried her best to draw him out of himself, but it was not often that she could divert him from his misery. What relieved him most was sleep, when he could obtain it; and, to recruit his powers, he was accustomed to take from nine to eleven hours sleep at night, besides naps during the day. When Boulton had erysipelas, in Cornwall, and could not stir abroad, he wrote to his partner complaining of an unusual lowness of spirits, on which Watt undertook to be his comforter in his own peculiar way. “There is no pitch of low spirits,” said he, “that I have not a perfect notion of, from hanging melancholy to peevish melancholy: conquer the devil when he is young.” Watt experienced all the tortures of confirmed dyspepsia, which cast its dark shadow over the life of every day. His condition was often most pitiable. It is true, many of the troubles which beset him were imaginary, but he suffered from them in idea as much as if they had been real. Small evils fretted him, and great ones overwhelmed him. He met them all more than halfway,