During this and part of the next year Cairns remained in Mr. Donaldson’s family, and his relations with that family as a whole, as well as his special work in the tuition of the young son and daughter of the house, were of the most agreeable kind.  He had by this time, however, formed some intimate friendships in Edinburgh, and there were several pleasant and interesting houses that were always open to him.  One of these deserves special mention.  Among his most intimate College friends was James McGibbon Russell, a distinguished student of Sir William Hamilton, and one of the founders of the Metaphysical Society.  Russell was the son of a Perthshire parish minister, but his parents were dead, and he lived with an uncle and aunt, Mr. and Mrs. Archibald Wilson, whose own family consisted of two sons and three daughters.  Cairns was introduced by Russell to the Wilson family, and soon became intimate with them.  His special friend—­at last the dearest friend he had in this world—­was the younger son, George, afterwards the well-known chemist and Professor of Technology in the University of Edinburgh.  No two men could be less alike—­George Wilson with a bright, alert, nimble mind; Cairns with an intellect massive like his bodily frame, and characterised chiefly by strength and momentum; and yet the two fitted into each other, and when they really got to know each other it might truly be said of them that the love between them was wonderful, passing the love of women.

By the midsummer of 1840 Cairns had come to a final decision about his future calling.  “I have,” he wrote to his father on 13th June, “after much serious deliberation and prayer to God for direction, made up my mind to commence this year the study of divinity, with a view to the office of the ministry of the Gospel.  I pray you, do implore the grace of God on my behalf, after this very grave and solemn determination.”

The Secession Church, to which he belonged, and to whose ministry he desired to seek admission, had no theological tutors who were set apart for the work of teaching alone.  Its professors, of whom there were four, were ministers in charges, who lectured to the students during the two holiday months of August and September.  The curriculum of the “Divinity Hall,” as it was called, consisted of five of these short sessions.  During the remaining ten months of each year the student, except that he had to prepare a certain number of exercises for the Presbytery which had him under its charge, was left very much to do as he pleased.

Cairns entered the Hall, at that time meeting in Glasgow, in the August of 1840.  Of the four professors who were on the staff of the institution, and all of whom were capable men, only two need here be mentioned.  These were Dr. Robert Balmer of Berwick and Dr. John Brown of Edinburgh.  Dr. Balmer was a clear-headed, fair-minded theologian—­in fact, so very fair, and even generous, was he wont to be in dealing