But, first, it is desirable that readers not acquainted with the circumstances and conditions of Stevenson’s parentage and early life should be here, as briefly as possible, informed of them. On both sides of the house he came of capable and cultivated stock. His grandfather was Robert Stevenson, civil engineer, highly distinguished as the builder of the Bell Rock lighthouse. By this Robert Stevenson, his three sons, and two of his grandsons now living, the business of civil engineers in general, and of official engineers to the Commissioners of Northern Lights in particular, has been carried on at Edinburgh with high credit and public utility for almost a century. Thomas Stevenson, the youngest of the three sons of the original Robert, was Robert Louis Stevenson’s father. He was a man not only of mark, zeal, and inventiveness in his profession, but of a singularly interesting personality; a staunch friend and sagacious adviser, trenchant in judgment and demonstrative in emotion, outspoken, dogmatic,—despotic, even, in little things, but withal essentially chivalrous and soft-hearted; apt to pass with the swiftest transition from moods of gloom or sternness to those of tender or freakish gaiety, and commanding a gift of humorous and figurative speech second only to that of his more famous son. Thomas Stevenson was married to Margaret Isabella, youngest daughter of the Rev. Lewis Balfour, for many years minister of the parish of Colinton in Midlothian. This Mr. Balfour (described by his grandson in the essay called ‘The Manse’) was of the stock of the Balfours of Pilrig, and grandson to that James Balfour, professor first of moral philosophy, and afterwards of the law of nature and of nations, who was held in particular esteem as a philosophical controversialist by David Hume. His wife, Henrietta Smith, a daughter of the Rev. George Smith of Galston, to whose gift as a preacher Burns refers scoffingly in the _Holy Fair_, is said to have been a woman of uncommon beauty and charm of manner. Their daughter, Mrs. Thomas Stevenson, suffered in early and middle life from chest and nerve troubles, and her son may have inherited from her some of his constitutional weakness as well as of his social and intellectual vivacity and his taste for letters. Robert Louis (baptized Robert Lewis Balfour) Stevenson was born on November 13, 1850, at 8 Howard Place, Edinburgh, and was the only child of his parents. His health was infirm from the first, and he was with difficulty kept alive by the combined care of a capable and watchful mother and a perfectly devoted nurse, Alison Cunningham; to whom his lifelong gratitude will be found touchingly expressed in the course of the following letters. In 1858 he was near dying of a gastric fever, and was at all times subject to acute catarrhal and bronchial affections and extreme nervous excitability. In January 1853 his parents moved to 1 Inverleith Terrace, and in May 1857