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stations, or the selection of new ones ; and secondly, with how few 

 new or revived establishments, with how limited a scale as to extent 

 and expense, and with how short a period as to the minimum term 

 of their duration, the expectation of these advantages being secured 

 could be compatible, and finally to fix upon the stations most 

 desirable. 



As regards the first point referred to, viz. the more complete 

 establishment of the laws themselves, and the giving of greater 

 numerical precision to their expression, the Committee are of opinion 

 that the laws themselves are not likely to be subverted or contra- 

 dicted by a larger series of observations at any station for which they 

 have once been shown to prevail ; but that every new station differing 

 much in geographical situation from the former, in which they might 

 be found verified, with or without supplementary modifications, would 

 undoubtedly add strength to the induction by which they have been 

 concluded. Additional numerical precision on the other hand would 

 only be attained by a continuance of observations at former stations, 

 and is not a point of sufficient importance, in their opinion, to be en- 

 titled to any weight in opposition to considerations in favour of 

 change, while in the one important case in which such additional 

 precision is especially desirable, that of the solar period, such addi- 

 tional precision will be acquired ultimately as a matter of course by 

 continued observation at any one of the existing permanent observa- 

 tories, of whose business magnetic observation forms a part as well 

 as by any amount of Colonial establishments. 



It is therefore mainly in the elucidation of obscure and difficult 

 physical points, and in the probable extension of our knowledge of 

 the geographical and other conditions on which the irregular dis- 

 turbances depend, that our hope of advantage from further observa- 

 tion consists ; our conviction being that, without special observations 

 at well-selected stations (selected, that is, with a view to these objects), 

 there is little or no prospect of further progress. The general cha- 

 racter of the magnetic phenomena may be considered as secured from 

 loss ; but the great problem remains unresolved, the local influences 

 are yet to trace, and the only means of tracing them must consist in 

 varying the position of our stations, so as to embrace great differences 

 in geographical situation, and in conformity with such indications as 

 can be gathered from our present experience. The magnetic esta- 



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