1 REPORT 1871. 



Report of the Kew Committee of the British Association for the 

 Advancement of Science for 1870-71. 



The Committee of the Kew Observatory submit to the Council of the British 

 Association the follomng statement of their proceedings during the past 

 year : — 



(A) WOEK BONT! BY KeW ObSEEVATORT UNDER THE DIRECTION OF THE 



British Association. 



1. Magnetic ivorlc. — In their last Eeport the Committee stated the plan on 

 ■which they proposed to reduce their Magnetic observations ; they now report 

 that with reference to the reduction of the Magnetic Disturbances from 

 January 1865 to December 1869, the period foUowing that which has already 

 been published, the discussion of Declination and Horizontal Force Disturb- 

 ances is nearly ready for presentation to the Eoyal Society, and that of the 

 Vertical Force is in progress ; when that is completed, the whole period, 1865 

 to 1869 inclusive, will have been discussed at Kew. The tabular statement, 

 which is herewith presented (see Appendix I.), exhibits the exact state of 

 the reduction. 



Two Dipping-needles by Dover and one by Adie have been tested for Mr. 

 Chambers, Superintendent of the Colaba Observatory ; and one needle has 

 been procured from Dover and tested for Prof. JeUnek, of Vienna. 



A Dip-circle by Dover has been verified and forwarded to Prof. Jelinek, 

 ■who ordered it on behalf of the K. K. mUitiir-geograpliisches Institut. 



Major-General Lefroy, Governor of Bermuda, having applied for the loan 

 of a Dip-circle, one has now been prepared for his use, and will be forwarded 

 to Bermuda as soon as possible. A Dip-circle has been obtained from Dover, 

 and, after verification, ^vill be forwarded to the Survey Department, Lisbon. 



At the request of Prof. Jelinek the Committee have undertaken to examine 

 a Dip-circle by Eepsold. It is of a large size and has eight needles, but Prof. 

 Jelinek reports that the results obtained by them are very discordant. 



Copies of certain specified maguetograph curves have been made and for- 

 warded to the late Sir J. Herschel, M. DiamiUa Miiller, of Florence, and Senhor 

 CapeUo, of Lisbon, at the request of those gentlemen. 



The usual monthly absolute determinations of the magnetic elements con- 

 tinue to be made by Mr. "\Miipple, the Magnetic Assistant. 



The Self-recording Magnetographs are in constant operation as heretofore, 

 also nuder his charge. 



2. Meteorological ivorh. — The meteorological work of the Observatory 

 continues in the charge of Mr. Baker. 



Since the Liverpool Meeting, 113 Barometers (including 17 Aneroids) have 

 been verified, and 2 rejected ; 1320 Thermometers and 215 Hydrometers have 

 like^wise been verified. 



Two Standard Thermometers have been constructed for Owens College, 

 Manchester, one for the Bugby School, one each for Profs. Harkness and 

 Eastmanu, of the Washington Observatory, four for Dr. Draper, of the New 

 York Central Park Observatory, one for Major Norton, of the Chief Signal 

 Office, "Washington, one for Mr. G. J. Symons, and three for the Meteorolo- 

 gical Committee. 



Three Thermograph Thermometers have been examined for Mr. Chambers, 

 of the Colaba Observatory, and three for the Meteorological Committee. 



