In London he was acquainted with many of the leading artists and persons interested in art.  Of the “teachers” of the day he was known to men so diverse as Carlyle—­and Maurice, with whom he corresponded in 1815 about his “Notes on Sheepfolds”—­and C.H.  Spurgeon, to whom his mother was devoted.  He was as yet neither a hermit, nor a heretic:  but mixed freely with all sorts and conditions, with one exception, for Puseyites and Romanists were yet as heathen men and publicans to him; and he noted with interest, while writing his review of Venetian history, that the strength of Venice was distinctly Anti-Papal, and her virtues Christian but not Roman.  Reflections on this subject were to have formed part of his great work, but the first volume was taken up with the a priori development of architectural forms; and the treatment in especial of Venetian matters had to be indefinitely postponed, until another visit had given him the opportunity of gathering his material.

Meanwhile, his wide sympathy had turned his mind toward a subject which then had received little attention, though since then loudly discussed—­the reunion of (Protestant) Christians.

He put together his thoughts in a pamphlet on the text “There shall be one fold and one Shepherd,” calling it, in allusion to his architectural studies, “Notes on the Construction of Sheepfolds.”  He proposed a compromise, trying to prove that the pretensions to priesthood on the high Anglican side, and the objections to episcopacy on the Presbyterian, were alike untenable; and hoped that, when once these differences—­such little things he thought them—­were arranged, a united Church of England might become the nucleus of a world-wide federation of Protestants, a civitas Dei, a New Jerusalem.

There were many who agreed with his aspirations:  he received shoals of letters from sympathizing readers, most of them praising his aims and criticising his means.  Others objected rather to his manner than to his matter; the title savoured of levity, and an art-critic writing on theology was supposed to be wandering out of his province.  Tradition says that the “Notes” were freely bought by Border farmers under a rather laughable mistake; but surely it was no new thing for a Scotch reader to find a religious tract under a catching title.  There were a few replies; one by Mr. Dyce, who defended the Anglican view with mild persiflage and the usual commonplaces.  And there the matter ended, for the public.  For Ruskin, it was the beginning of a train of thought which led him far.  He gradually learnt that his error was not in asking too much, but in asking too little.  He wished for a union of Protestants, forgetting the sheep that are not of that fold, and little dreaming of the answer he got, after many days, in “Christ’s Folk in the Apennine.”

Meanwhile the first volume of “Stones of Venice” had appeared, March, 1851.  Its reception was indirectly described in a pamphlet entitled “Something on Ruskinism, with a ‘Vestibule’ in Rhyme, by an Architect” complaining bitterly of the “ecstasies of rapture” into which the newspapers had been thrown by the new work: