of a journey or two abroad, till 1652.  “Nor am I here altogether idle,” he says in one of his latest letters to Hartlib from Stalbridge; “for I can sometimes make a shift to snatch from the importunity of my affairs leisure to trace such plans, and frame such models, as, if my Irish fortune will afford me quarries and woods to draw competent materials from to construct after them, will fit me to build a pretty house in Athens, where I may live to Philosophy and Mr. Hartlib.”  The necessity of looking after the Irish fortune of which he here speaks had since then taken him to Ireland and kept him there for the greater part of two years.  He found it, he says, “a barbarous country, where chemical spirits were so misunderstood, and chemical instruments so unprocurable, that it was hard to have any Hermetic thoughts in it;” and he had betaken himself to “anatomical dissections” as the only kind of scientific pastime that Irish conditions favoured.  On returning to England, in 1654, he had settled in Oxford, to be in the society of Wilkins, Wallis, Goddard, Ward, Petty, Bathurst, Willis, and other kindred scientific spirits, most of them recently transferred from London to posts in the University, and so forming the Oxford offshoot of the Invisible College, as distinct from the London original.  But still from Oxford, as formerly from Stalbridge, the young philosopher made occasional visits to London; and always, when there, he was to be found at the house of his sister, Lady Ranelagh.—­What property belonged to Lady Ranelagh herself, or to her husband, lay also mainly in Ireland; but for many years, in consequence of the distracted state of that country, her residence had been in London.  “In the Pall Mall, in the suburbs of Westminster,” is the more exact designation.  Her Irish property seems, for the present, to have yielded her but a dubious revenue; and though she had a Government pension of L4 a week on some account or other, she seems to have been dependent in some degree on subsidies from her wealthier relatives.  It also appears, though hazily, that there was some deep-rooted disagreement between her and her husband, and that, if he was not generally away in Ireland, he was at least now seldom with her in London.  She had her children with her, however.  One of these was her only son, styled then simply Mr. Richard Jones, though modern custom would style him Lord Navan.  In 1655 he was a boy of fifteen years of age, Lady Ranelagh herself being then just forty.  The education of this boy, and of her two or three girls, was her main anxiety; but she took a deep interest as well in the affairs of all the members of the Boyle family, not one of whom would take any step of importance without consulting her.  She corresponded with them all, but especially with Lord Broghill and the philosophical young Robert, both of them her juniors, and Robert peculiarly her protege.  In his letters to her, all written carefully and in a strain of stately and respectful affection, we see