He was endowed by nature with a strong constitution and a robust frame, but there is reason to apprehend that he tasked his mental powers too laboriously by his intense and continuous application to study during his long periods of seclusion at Austhorpe. As he advanced in years his sturdy strength of limb departed, and his physical powers gave way, while he was yet in his mature manhood. They were further impaired by the abstemious regimen which he was subsequently compelled to adopt. [Sidenote: The dreaded enemy.] Cerebral disease, moreover, was hereditary in his family, and he long dreaded the attack of paralysis, which eventually terminated his life. But, as Mr. Smiles says, this only made him the more eager to employ to the greatest advantage the time which it might yet be permitted him to live: and he dreaded above all things the blight of his mental powers--to use his own words, "lingering over the dregs after the spirit had evaporated"--chiefly as depriving him of the means of doing further good. The last public measure on which he was professionally engaged in London was the passing of a Bill through Parliament for the construction of the Birmingham and Worcester Canal. The opposition to it was fierce and protracted, and his support of the measure in committee entailed upon him great application, anxiety, and thought, His friends saw with much concern that the labour was too great for him, and were in constant alarm lest the powers of his vigorous mind should suddenly give way. The Bill, however, passed by a small majority, and Smeaton retired to his house at Austhorpe to enjoy the rest he so greatly needed. [Sidenote: Smeaton's last days.] On the 16th of September the blow fell. He was seized with an attack of paralysis while walking in the garden. Happily he regained the use of his mental faculties, and was able to thank the Almighty that his intellect was spared. During his illness he dictated several letters to his old friend, Mr. Holmes, in which he minutely described his health and feelings. In one of them he says pathetically, "I conclude myself nine-tenths dead, and the greatest favour the Almighty can do (as I think), will be to complete the other part; but as it is likely to be a lingering illness, it is only in his power to say when that is likely to happen."