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Prof. B. Stewart and Mr. W. L. Carpenter. [Feb. 25, 



Results of Comparison around 26 Days. 



6. Comparison as to Duration of Period. — This is exhibited in 

 Table III, which is precisely analogous to Table I. The same remarks, 

 too, are applicable to both tables, and it will be observed that here, 

 as in the former table, the positions of maximum Inequality for sun- 

 spots, are, on the whole, near those for Toronto temperature and 

 Prague declination. Nor is there, in our opinion, a greater corre- 

 spondence between sun-spots and declination-ranges than between 

 sun-spots and temperature-ranges. 



7. Comparison in Phase. — This comparison is exhibited in Table IV, 

 which is precisely analogous to Table VI of our previous communica- 

 tion, except that here we have introduced the Inequality —52, which 

 we had omitted from Table VI, because the Toronto Inequality 

 was not sufficiently near the type. It will be noticed from Table IV, 

 that at least as far as regards the Toronto declination, the constancy 

 of phase is not so evident as for the Inequalities around 24 days. It 

 will likewise be remarked, that while the chief Toronto declination 

 maximum, like that for Inequalities around 24 days, follows a little 

 after the sun-spot maximum, the chief Prague declination maximum 

 decidedly precedes the other two. It thus appears that the similarity 

 in time of maximum between the two declination stations which 

 holds for Inequalities around 24 days (Table II) does not hold for 

 Inequalities around 26 days. 



Broadly speaking, in both cases there are appearances of duplicity 

 of phase, but in the case of Toronto the same maximum has remained 

 the predominant one in both tables, while in the case of Prague the 

 predominant maximum for the 24-day Inequalities has become the 

 subsidiary maximum for those around 26 days. 



8. In attempted explanation of this we would in the first place 

 desire to repeat the remark we made in our previous communication, 

 namely, that there are two possible kinds of periodicity with regard 

 to sun-spots, and that it is not necessary to regard the Inequali- 

 ties around 24 days and those around 26 days as perfectly 

 similar phenomena. Again, as regards the evidence we gave 

 in a footnote to that communication, tending to show that the 

 Inequalities around 26 days might denote the synodic periods with 

 respect to the earth of those around 24 days, this evidence is, 

 we find, borne out by the declination results. We prefer, however, 

 to wait until we have accumulated more information before we venture 

 to discuss this important subject. Meanwhile we shall content our- 

 selves with remarking that the similarity between the two stations, 

 Toronto and Prague, for the one set of magnetic Inequalities, and 

 their dissimilarity for the other, is at first sight in favour of the 

 theory of a physical difference of some sort between the two. We 



