"It had been the sober belief of Descartes that the life of man could be prolonged, not, indeed, on this earth, to eternal duration, but to what he called the age of the patriarchs, and modestly defined to be from 100 to 150 years average length. Well, even this dream of sages was here fulfilled—nay, more than fulfilled; for the vigour of middle life was preserved even after the term of a century was passed. With this longevity was combined a greater blessing than itself—that of continuous health. (Chapter XXVI)"