In his seventy-first year Edgeworth had a dangerous illness, and though he seemed to recover from it for a time, he never regained his former strength.

One great privation was that, from the failure of his sight, he became dependent on others to read and write for him.

But his cheerful fortitude did not fail, though he felt that his days were numbered.

He had promised to try some private experiments for the Dublin Society, and with the help of his son William he carried out a set of experiments on wheel carriages in April 1815 and in May 1816.
Almost his last literary effort was to dictate some pages which he contributed to his daughter Maria's novel Ormond, and he delighted in having the proofsheets read to him and in correcting them.

Mrs.
Ritchie has given some touching details of his last days in her Introduction to a new edition of Ormond.
Maria writes:--'The whole of Moriaty's history, and his escape from prison, were dictated without any alteration, or hesitation of a word, to Honora and me.