But Mitchell was never long healthy. He was a sickly boy from his youth and, in his adult life, he frequently complained of pulmonary problems. Still, he lived a varied and interesting life, serving for a time as Consul to Venice, edited at least two periodicals in New York, became a landscape gardener and architect, and was granted a Doctor of Laws from Yale in 1878 (he also dedicated the university's Woodbridge Hall, taught a course off and on, and had his portrait hanging in the dining hall for a time). An area of New Haven, Edgewood, was named after his home.
By his 80s, Mitchell was significantly less active. When doctors presumed he had a hemorrhage in his lungs, Mitchell knew the end was near, even as he became less cognizant of his surroundings. Looking out the window of his home of 50 years one day, he said, "I used to know this place, and it was beautiful." He died in his library. He was buried in Woodbridge, Connecticut, and marked with a headstone of his own design. From A Dream Life:
Death levels the capacities of the living as it levels the strength of its victims. It is as grand to the man as to the boy; its teachings are as deep for age as for infancy.
You may learn its manner, and estimate its approaches; but when it comes, it comes always with the same awful front that it wore to your boyhood. Reason and Revelation may point to rich issues that unfold from its very darkness; yet all these are no more to your bodily sense, and no more to your enlightened hope, than those foreshadowings of peace which rest like a halo on the spirit of the child as he prays in guileless tones,—Our Father, Who Art In Heaven!
It is a holy and a placid grief that comes over you;—not crushing, but bringing to life from the grave of boyhood all its better and nobler instincts. In their light your wild plans of youth look sadly misshapen; and in the impulse of the hour you abandon them; holy resolutions beam again upon your soul like sunlight; your purposes seem bathed in goodness. There is an effervescence of the spirit that carries away all foul matter, and leaves you in a state of calm that seems kindred to the land and to the life whither the sainted mother has gone.
This calm brings a smile in the midst of grief, and an inward looking and leaning toward that Eternal Power which governs and guides us;—with that smile and that leaning, sleep comes like an angelic minister, and fondles your wearied frame and thought into that repose which is the mirror of the Destroyer.