During 1906, as indeed until his death, he was carrying on a constant correspondence with Prof. Stevenson of New York, in which many questions--geological, social, political, personal, and so forth--came up for discussion. Thus in January 1906 he says, speaking of his sons and their careers:--“All the birds are out of our nest now, all save one wee lassie who remains to brighten our hearts with laughter and song.” By this time his eldest son was established in a practice at Ayr, the next two were working as mining engineers in Borneo, and the youngest was studying music in Germany. During this year the rheumatic knee still troubled him, and a visit to Harrogate to try the waters there did not produce much permanent benefit. The summer was spent in Ayrshire, but was saddened by the sudden death of a favourite niece, who had been almost a daughter of the house during the long years when the family consisted only of boys, and was on holiday with her uncle and aunt at the time of the acute illness which caused her death. In 1907 his eldest son was married, and there is a charming letter written to him on his wedding tour, with much wise advice about matrimony, mingled with personal experiences. Among other things the writer says:--“When I went on my honeymoon I took a geological hammer with me, but the geology did not count for much. I think the hammer was used chiefly for digging up roots and ferns for your mother, or for knocking off bits of rock that were covered with gay lichens.” The young couple had gone to Devonshire, and this sent the father back to Herrick, and that writer’s description of “dull Devonshire.” In the autumn Prof. Geikie had the pleasure of meeting Prof. Stevenson of New York, who came to London for the Centenary Celebration of the Geological Society there. At the end of November he writes to his eldest son, saying:--“My work at College is easy this winter, for I feel in much better health than I have done for two or three years. My lameness is practically cured, and I begin to think that I may yet be able to go with May to her first ball, and dance a reel with the nicest-looking girl in the room--as usual.” In the spring of 1908 Prof. and Mrs Geikie and their daughter, together with a niece, went to Portugal, which they all enjoyed greatly. In the early part of this year also the first grandchild, a little girl, was born. Another event of the year was the translation of _Structural Geology_ into French. The correspondence with Prof. Stevenson was still going on, and there was an interesting letter from the latter in August. He was contemplating retiral from his professorship, while Prof. Geikie had no wish to give up his own post, and the two discussed the question of the desirable age for the event. Prof. Stevenson wished to have leisure to complete some private work of his own, and his letter contains the following interesting passage:--