During the two years which immediately preceded the cessation of my official life, my wife and I were working together at the "Liberty." I had first planned and written it as a short essay in 1854. It was in mounting the steps of the Capitol, in January, 1855, that the thought first arose of converting it into a volume. None of my writings have been either so carefully composed, or so sedulously corrected as this. After it had been written as usual twice over, we kept it by us, bringing it out from time to time, and going through it _de novo_, reading, weighing, and criticizing every sentence. Its final revision was to have been a work of the winter of 1858-9, the first after my retirement, which we had arranged to pass in the south of Europe. That hope and every other were frustrated by the most unexpected and bitter calamity of her death--at Avignon, on our way to Montpellier, from a sudden attack of pulmonary congestion. Since then I have sought for such allevation as my state admitted of, by the mode of life which most enabled me to feel her still near me. I bought a cottage as close as possible to the place where she is buried, and there her daughter (my fellow-sufferer and now my chief comfort) and I, live constantly during a great portion of the year. My objects in life are solely those which were hers; my pursuits and occupations those in which she shared, or sympathized, and which are indissolubly associated with her. Her memory is to me a religion, and her approbation the standard by which, summing up as it does all worthiness, I endeavour to regulate my life. After my irreparable loss, one of my earliest cares was to print and publish the treatise, so much of which was the work of her whom I had lost, and consecrate it to her memory. I have made no alteration or addition to it, nor shall I ever. Though it wants the last touch of her hand, no substitute for that touch shall ever be attempted by mine.