REPORT OF THE KEW COMMITTEE. XXXUl 



(10) The Council are informed that Invitations will be presented to the 

 General Committee at its Meeting on Monday, September 9, to hold the next 

 meeting in Cambridge. The invitations formerly offered on the part of 

 Birmingham and Newcastle-on-Tyne will be renewed on this occasion ; and 

 other invitations will be presented from Bath and Nottingham. 



Report of the Keio Committee of the British Association for the 

 Advancement of Science for 1860-1861. 



The Committee of the Kew Observatory beg to submit to the Association 

 the following Report of their proceedings during the past year. 



It was noticed in a previous Report that General Sabine had undertaken 

 to tabulate the hourly values of the magnetic elements from tlie curves given 

 by these instruments. These values have been reduced under his super- 

 intendence, and some of the results have been embodied in the following 

 papers which he has communicated to the Royal Society : — 



(1) On the Solar-diurnal Variation of the Magnetic Declination at Pekin. 

 — Proceedings of the Royal Societ)', vol. x. p. 360. 



(2) On the Laws of the Phenomena of the larger Disturbances of the 

 Magnetic Declination in the Kew Observatory : with notices of the progress 

 of our knowledge regarding the Magnetic Storms. — Proceedings of the 

 Royal Society, vol. x. p. 624. 



(3) On the Lunar-diurnal Variation of the Magnetic Declination obtained 

 from the Kew Photograms in the years 1858, 1839, and 1860. — Proceedings 

 of the Royal Society, vol. xi. p. 73. 



The Superintendent, Mr. Stewart, has also communicated to the Royal 

 Society a description of the great magnetic storm at the end of August and 

 beginning of September 1859, deduced from the Kew Photographs. 



Mr. Chambers continues to be zealously employed in the magnetical de- 

 partment, and attends to the self-recording magnetographs, which have been 

 maintained in constant operation. 



The usual monthly absolute determinations of the magnetic elements con- 

 tinue to be made ; and the dip observations from November 1857 to the 

 present date (282 in all), a large portion of which were made by the late 

 Mr. Welsh and Mr. Chambers, have been made available by General Sabine 

 in connexion with some previous observations of his own for determining 

 the secular change in the magnetic dip in London, between the years 1821 

 and 1860. See Proceedings of the Royal Society, vol. xi. p. 144. 



The instruments for the Dutch Government alluded to in the last Report 

 have been verified at Kew and taken away. They consisted of a set of self- 

 recording magnetographs with a tabulating instrument, two Dip Circles, and 

 one Fox's Dip Circle for Dr. Bergsma ; also of two Unifilars, one for Dr. 

 Bergsma and one for Dr. Buys Ballot. 



Shortly after the despatch of these instruments, another set of self-record- 

 ing Magnetographs were received at Kew, in order to be tested previous to 

 their being sent to Dr. Bache, of the United States, and these were despatched 

 in the early part of this year to America, along with a tabulating instrument, 

 a Unifilar, and Dip Circle, all of which were verified at Kew. 



The staff at Kew are at present occupied with a third set of these instru- 

 ments, along with a Dip Circle and Unifilar, for the University of Coimbra ; 

 and Prof. Da Souza of that University is engaged at present at the Kew 

 Observatory in examining his instruments, and in receiving instructions 

 regarding them. 



It will thus be seen that no fewer than three sets of these instruments 

 1861. . c 



