presents itself to my mind; the waste of labour in the repetition of observations at different observatories.....  I think that this consideration ought not to be put out of sight in planning the courses of different Observatories.”—­In this year De Launay’s Lunar Theory was published.  This valuable work was of great service to Airy in the preparation of the Numerical Lunar Theory, which he subsequently undertook.—­In the latter part of this year Airy was elected President of the Royal Society, and held the office during 1872 and 1873.  At this time he was much pressed with work, and could ill afford to take up additional duties, as the following quotation from a letter to one of his friends shews:  “The election to the Presidency of R.S. is flattering, and has brought to me the friendly remembrances of many persons; but in its material and laborious connections, I could well have dispensed with it, and should have done so but for the respectful way in which it was pressed on me.”

Of private history:  There was the usual winter visit to Playford.—­In April he made a short trip to Cornwall with his daughter Annot.—­In June he was appointed a Companion of the Bath, and was presented at Court on his appointment.—­Mrs Airy was staying with her daughter, Mrs Routh, at Hunstanton, during June, her state of health being somewhat improved.—­From August 1st to 28th he was chiefly in Cumberland, at Barrow House, and at Grange, Borrowdale, where his son Osmund was staying for a holiday.

1872

“From the Report to the Board of Visitors it appears that ’The Normal Siderial Clock for giving sidereal time by galvanic communication to the Astronomical Observatory was established in the Magnetic Basement in 1871, June; that locality being adapted for it on account of the uniformity of temperature, the daily changed of temperature rarely exceeding 1 deg.  Fahrenheit.  Its escapement is one which I suggested many years ago in the Cambridge Transactions; a detached escapement, very closely analogous to the ordinary chronometer escapement, the pendulum receiving an impulse only at alternate vibrations....  The steadiness of rate is very far superior to any that we have previously attained.’—­The aspect of railway enterprise is at present favourable to the Park and to the Observatory.  The South-Eastern Railway Company has made an arrangement with the Metropolitan Board of Works for shifting the course of the great Southern Outfall Sewer.  This enables the Company to trace a new line for the railway, passing on the north side of London Street, at such a distance from the Observatory as to remove all cause of alarm.  I understand that the Bill, which was unopposed, has passed the Committee of the House of Commons.  I trust that the contest, which has lasted thirty-seven years, is now terminated.—­The observations of 7 Draconis with the Water-Telescope, made in the autumn of 1871, and the spring of 1872, are reduced, the latter only in their first steps....  Using