372 



Report of the Kew Committee, 



operation under the care of Mr. T. W. Baker, assisted by T. Grunter. 

 The daily standard eye-observations for the control of the automatic 

 records have been made regularly, as well as daily observations in con- 

 nexion with the Washington synchronous system. 



In addition to the regular work of Kew as one of the self-recording 

 Observatories in connexion with the Meteorological Office, the duty of 

 examining and checking the work of the six other self-recording Obser- 

 vatories of the same character has been carried on, in accordance mth 

 the method described in the Eeport of the British Association for 1869. 

 This portion of the work has been performed of late by Messrs. Hawkes- 

 worth, Aldridge, and Harrison. 



The arrears of work, caused by the removal of Mr. Cullum to the charge 

 of the Valencia Observatory, have been cleared off, and the work is now 

 up to date. 



The Observatories at Aberdeen, Armagh, Falmouth, Griasgow, Stony- 

 hurst, and Valencia have been visited by Mr. Whipple, and their instru- 

 ments inspected. 



Electrometer. — This instrument having experienced an accidental 

 derangement in June has since failed in its action, and all attempts at 

 setting it to work satisfactorily have been hitherto unsuccessful. The 

 maker, Mr. White, of G-lasgow, has promised to visit the Observatory at 

 an early date*and examine it to find the cause of failure. 



A determination of the scale-value of the Electrometer by means of 

 a 100-cell Bunsen battery was made in January. 



Photoheliograph. — The Photoheliograph having been replaced in the Eoyal 

 Observatory, Greenwich, by one of the instruments constructed for use 

 in the Transit-of- Venus expeditions, was returned to the Observatory 

 January 5th, and re-erected in the Dome, but was again dismounted in 

 March, and sent, together with a number of solar negatives, to the Loan 

 Exhibition, South Kensington, where it now remains. 



The re-examination of the measurements of the Kew sun-pictures, as 

 noticed in former Reports, has been steadily carried on throughout the 

 year by Mr. Whipple, assisted by Mr. M'Laiighlin, who has been tem- 

 porarily engaged for this purpose; and the Ephemerides for the whole 

 period of the Kew Sun-Spot Observations have been recalculated by Mr. 

 A. Marth, and are now in the Observatory. All of these operations have 

 been conducted at the expense of Mr. De La Eue. 



A new Micrometer for use in India, with a PhotoheUograph, has been 

 made under the supervision of Mr. De La Eue, in which various modi- 

 fications, suggested by experience obtained in the use of the instrument 

 at Kew, have been introduced. 



At the request of Mr. Hind, E.E.S., a careful inspection has been 

 made of the Kew sun-pictures from 1858 to 1875, with a view to obtain 

 evidence as to the existence of the intra-Mercurial planet. The observa- 

 tions bearing on the question have been communicated to that gentleman. 



