REPOKT or THE COUNCIL. 



" British Association for the Advancement of Science, 

 22 Albemarle Street, W., November 27th, 1872. 



" My Lord Duke, — On behalf of the British Association, I have the honour 

 to urge upon your Grace's consideration the importance of making adequate 

 preparation in India for the observation of the Transit of Venus in 1874, as 

 •well as of making provision for the continuation of solar observations in India, 

 a matter to -which the Council attach special importance. 



" The observations ought to comprise both eye and photograpliie records ; 

 and the following instruments are specially recommended by the Council as 

 those which it is desirable to procure at once. The photographic records 

 shoiild be made in the manner determined upon by the Astronomer Royal 

 and by M. Otto Struve for the llussian Government — namely, by means of a 

 Photoheliograph, on the principle of the instrument which has been worked 

 at the Ivew Observatory during ten years, but improved both in the optical 

 and mechanical parts. 



" Tor eye-observations it will be desirable to have a Telescope of the greatest 

 excellence, of 6-iuch aperture, mounted cquatorially iu the best manner, with 

 a clockwork driver. It is also desirable to have a 4-iuch telescope, mounted 

 cquatorially, and driven by clockwork. 



'* A transit instrument with clock, and one or two chronometers, and also 

 an Altazimuth Instrument. 



"As the 6-inch equatorial would be available afterwards for Sun Observa- 

 tions, it would be desirable to fit it with a Spectroscope of sufiicient dispersive 

 power to permit of the prominences being observed efficiently. 



"The Council would recommend that the Heliograph should be worked 

 continuously iu India, inasmuch as such records are calciilated to throw 

 much light upon the causes of climatic changes, and it is impossible in any 

 one locality to secure a coutinuous record of the sun's activity : observations 

 of this nature are about to be proceeded with at the Eoyal Observatorj', 

 Greenwich ; but past experience has shown that, on the average, half the 

 days in the year are unproductive, and it is hoped that if India cooperates 

 the gaps may be filled up. 



" The Council of the Association trust that the importance of the subject 

 win induce your Grace to give the matter a favourable consideration. 

 " I have the honour to be, 

 «' My Lord Duke, 



" Your most obedient Servant, 



(Signed) " W. B. Caepenxeb, 



President of the Briiisli Association" 

 " Bis Grace The Bule of Argyll, K.G., 



Secretary of State for India." 



" India Office, 

 December 13th, 1872. 



" Sir,' — I am directed by the Secretary of State for India in Council to 

 acknowledge the receipt of yoiu- letter of the 27th ultimo, expressing the 

 desii'e of the Council of the British Association that provision may be made 

 in India for observation in that country of the Transit of Ycnus in 1874, 

 and for a continuation of solar observations in future, 



" In reply, I am desired by the Duke of Argyll to state that His Grace 

 has been in correspondence with the Astronomer Eoyal and the Government 

 of India with reference to an observation in Northern India of tlie Transit of 



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