462 BRITISH SCIENTIFIC ASSOCIATION, 



judged, equal to the present requirements of theoretical investigation. This }g 

 the more deserving of notice, because Toronto is a station where the casual and 

 periodical variations, which it was apprehended would seriously interfere with the 

 determination of absolute values, ate unusually large. We may derive, therefore* 

 from the results thus obtained, the greatest encouragement to persevere in a line 

 of research which is no longer one of doubtful experiment, and to give it that 

 further extension which the interests of science require. 



Amongst the results which have recompensed the labours of the. Colonial Obser- 

 vatories in this branch of their inquiries, perhaps there is none of more importance 

 in respect to the general theory of terrestrial magnetism, than the conclusion 

 which has been established by means of the observations of the Declination at St. 

 Helena, that the current annual amount of secular change takes place by equal 

 aliquot portions in every month, and even in every fortnight of the year. The 

 magnitude of the annual change of the Declination at St. Helena, 8' (or more pre- 

 cisely 7 '-93 in each of the eight years in which the observations were maintained), 

 and the comparative tranquillity of the tropical regions in regard to magnetic dis- 

 turbances, were circumstances which rendered St. Helena a particularly eligible 

 locality for an investigation of this nature. The result has been, to remove secular 

 change altogether from the category of atmospheric or thermic relations, with 

 which, in the absence of a correct knowledge of the facts, it has frequently been 

 erroneously associated ; and to show conclusively that it is a phenomenon of far 

 more systematic order and regularity than has been generally apprehended (Pro- 

 ceedings of the Royal Society, vol. vii. pp. 67-75). 



THE BRITISH ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE, 

 One of the most brilliant and successful meetings which have signalized the 

 progress of the British Association in the accomplishment of its important aims, 

 opened at Dublin on the 26th of August. Twenty-two years have elapsed since 

 last the Association graced the halls of the Irish Capital : and great as are the 

 changes every where noticeable in such a lapse of time, a more momentous epoch 

 has not occurred in the history of Ireland. To whatever city the Association 

 returns after such an interval, the survivors who bore a part in its deliberations 

 and discussions, must recall many former valued coadjutors now no more ; while 

 also the hopeful and cheering element is not wanting. The eager boy who theD 

 gratified his vague longings by a stolen peep into the sections, is now seen entering 

 as a scientific cadet, and doing duty on the local committee, or honored with a 

 special and recognized rank as a secretary of his favourite section ; while again 

 the youthful sectional secretary of former years, now steps down into the arena, 

 acknowledged as an equal among the veterans of science. 



After the usual preliminary business, including the reading of the Report of the 

 Council to the General Committee, and the presentation of the reports of the Kew 

 Observatory, the Parliamentary Committee, and the General Treasurer; the 

 members and friends of the association assembled in the Rotunda, where Professor 

 Daubeny resigned the chair to his successor, the Rev. Humphrey Lloyd, D. D. 



After some interesting reminiscences of a personal and local nature, with which 

 the President opened his Address, he thus proceeded in accordance with the well 



