of 50 lbs. on the square foot of Osler’s Anemometer was twice exceeded during this storm.—­With respect to the Diurnal Inequalities of Magnetic Horizontal Force:  Assuming it to be certain that they originate from the Sun’s power, not immediately, but mediately through his action on the Earth, it appears to me (as I suggested long ago) that they are the effects of the attraction of the red end or north end of the needle by the heated portions of our globe, especially by the heated sea, whose effect appears to predominate greatly over that of the land.  I do not say that everything is thus made perfectly clear, but I think that the leading phenomena may be thus explained.  And this is almost necessarily the way of beginning a science.—­In the first few years after the strict and systematic examination of competitive chronometers, beginning with 1856, the accuracy of chronometers was greatly increased.  For many years past it has been nearly stationary.  I interpret this as shewing that the effects of bad workmanship are almost eliminated, and that future improvement must be sought in change of some points of construction.—­Referring to the Transit of Venus in 1874, the printing of all sections of the Observations, with specimens of the printed forms employed, and remarks on the photographic operations, is very nearly completed.  An Introduction is begun in manuscript.  I am in correspondence with the Commission which is entrusted with the arrangements for observation of the Transit of 1882.—­The Numerical Lunar Theory has been much interrupted by the pressure of the Transit of Venus work and other business.”—­In his Report to the Board of Visitors (his 46th and last), Airy remarks that it would be a fitting opportunity for the expression of his views on the general objects of the Observatory, and on the duties which they impose on all who are actively concerned in its conduct.  And this he proceeds to do in very considerable detail.—­On May 5th he wrote to Lord Northbrook (First Lord of the Admiralty) and to Mr Gladstone to resign his post of Astronomer Royal.  From time to time he was engaged on the subject of a house for his future residence, and finally took a lease of the White House at the top of Croom’s Hill, just outside one of the gates of Greenwich Park.  On the 15th of August he formally resigned his office to Mr W.H.M.  Christie, who had been appointed to succeed him as Astronomer Royal, and removed to the White House on the next day, August 16th.

His holiday movements in the portion of the year up to August 16th consisted in his winter visit to Playford, from which he returned on Jan. 24th:  and a subsequent visit to Playford from June 7th to 18th.

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The following correspondence relating to Airy’s retirement from office testifies in a remarkable manner to the estimation in which his services were held, and to the good feeling which subsisted between him and his official superiors.