464 



Report of the Kew Committee. 



All of these operations have been conducted at the expense of Mr. De 

 La Rue. 



The eye- observations of the sun, after the method of Hofrath Schwabe, 

 have been made daily by Mr. Harrison, when possible, as described in 

 the Report for 1872, in order, for the present, to maintain the continuity 

 of the Kew record of sun-spots. 



Extra Observations. — The Solar-radiation Thermometers are still ob- 

 served daily. 



The Campbell Sundial, described in the 1875 Report, continues in 

 action, and the improved form of the instrument, giving a separate record 

 for every day of the duration of sunshine, has been regularly worked 

 throughout the year and its curves tabulated. 



Wind Component Integrator. — The Wind Component Integrator, an 

 instrument which automatically resolves the velocity of the wind into its 

 rectangular components, which was exhibited by Prof, von Oettingen, of 

 Dorpat, at the recent Loan Exhibition, having been lent by the Guarantors 

 of that Exhibition to the Meteorological Council, has been erected in the 

 sun-room of the Observatory at their expense. The instrument has been 

 temporarily attached to the existing anemograph, and its gearing so modi- 

 fied as to enable it to print from type-wheels on a strip of paper the 

 number of miles of wind passing over the building from the north, east, 

 south, and west during every half-hour*. 



At the request of the Editor of the ' Times,' a copy of the traces of 

 the self-recording instruments on a reduced scale, together with an 

 epitome of the general features of the weather, is now prepared. This 

 is published every week in that journal, the cost to the Observatory being 

 defrayed by the proprietors. 



Verifications. — This branch of the work of the Observatory has been 

 carried on with considerable success as usual. The following magnetic 

 instruments have been verified : — 



A set of Magnetographs for the Batavia Observatory. 



„ „ ,, Potsdam Observatory. 



A Collimator Magnet for Dr. van der Stok. 



A Dip-circle, with extra needles, for Vice-Admiral Sir Charles 

 Shad well. 



Two Azimuth Compasses for Mr. Erewen. 



There have also been purchased on commission and verified : — a Unifilar 

 for Dr. Da Souza, Coimbra ; a Collimator magnet for Mr. Kingston, To- 

 ronto ; a Dip-circle for Prof. Weihrauch, Dorpat ; a Dip-circle for Prof. 

 Houzeau, Brussels Observatory ; and two Dip-needles for Prof. Smirnow, 

 Kazan. There are also now undergoing verification a set of Magneto- 



* A complete description of this instrument, illustrated in detail, is to be found in 

 the ' Repertorium fur Meteorologie,' vol. v. No. 10, St. Petersburg, 1877. 



