Report of the Kew Committee. m 107 



which would be entailed to provide a suitable apparatus for use at Kew 

 would exceed the resources of the Observatory. These investigations 

 have therefore not been carried out hitherto. 



It has appeared desirable to replace the Cathetometer used in con- 

 nexion with the Standard Barometer by a new instrument ; and accord- 

 ingly such an apparatus is in process of construction. As soon as this 

 is completed it is intended to institute a comparison between the Stan- 

 dard Barometers at Kew and Greenwich, the Astronomer Koyal having 

 most readily consented to such an operation. 



Information on meteorological results has been supplied to Mr. Gr. J. 

 Symons, the Secretary of the Northern Institute of Mining Engineers, 

 Mr. K. J. Marks, and the Editor of the ' Illustrated London News.' 



Pendulum Apparatus. — In the use made of the Kew pendulum vacuum- 

 chamber by Capt. Heaviside, B/.E., in the course of the year 1874, it was 

 found that a certain amount of deterioration in the joints had taken 

 place. These have since been newly ground and rendered air-tight so as 

 to be ready for use. 



Mr. C. J. Peirce, of the United States Coast Survey, having made 

 through the Admiralty an application to the Boyal Society to be 

 allowed to swing his pendulums at Kew, has at once received permis- 

 sion, and the experiments will be undertaken in the course of the ensuing 

 year. 



Two Iron Tripods, which had been formerly used for swinging in- 

 variable pendulums, and had remained in store at Kew, were granted by 

 the Committee to the Hydrographer for the service of the Arctic Ex- 

 pedition. They were repaired at the expense of the Admiralty ; and 

 while one of them still remains at Kew, the other has been supplied to 

 the Expedition, together with the wooden clock-supports ; at the same 

 time an Astronomical Clock (Shelton, No. 35) was also supplied to the 

 Hydrographic Office. 



Chronometer Testing. — It has been under deliberation during the year 

 whether or not it would be advisable to institute at Kew an Office for 

 the testing and rating of Chronometers, of a similar character to that 

 conducted at Bidston Observatory by Mr. J. Hartnup. 



The President and Council of the British Horological Institute have 

 expressed themselves favourably to the proposal in a scientific point of 

 view ; but as yet no decision has been arrived at by the Committee. 



Instruction given. — Pour Officers from the Arctic Expedition attended 

 at Kew for instruction in the use of Magnetic instruments, and two 

 others for instruction in the swinging of pendulums and in the use of 

 the Transit-Instrument. The final observations of these gentlemen were 

 recorded for making Kew a base station. Certain modifications in the 

 absolute Magnetic instruments, designed by Mr. Whipple for adaptation 

 for use in high latitudes, have been effected to the satisfaction of the 

 Hydrographer. 



