Intelligence and Miscellaneous Articles. 561 



B is true to the 8th dec, C. to the 10th, D to the 16th, E to 

 the 18th. 



The converse : — 

 Write -050525 x 9 = '45472,5 —a 



7 a - 



io a 



•31830,75 



+ a - = 

 2-10 3 



22736,25 





31830,97736,25 



+ 1 a ~ 



1136,8125 



20*2-10 5 



+d °- x 4 = 



11368,125 



-*•*£ = 



-11,36812,500 



Sum = 



•31830,98861,80805,625 



Sum 

 10 11 



3183,099 



.-A- 



-198,944 





•31830,98861,83789,780 



Then 



•31830,98861,83790,671 



Error — 



-•00000,00000,00000,891 



39 Howland Street, 



London, 



October 15, 1862. 



S. M. Drach. 



ON THE SOLAR ENERGY AS MANIFESTED IN THE AUTUMN OF 1861 

 AND A PORTION OF THE SPRING OF 1862. BY W. R. BIRT, ESQ. 



During the summer of 1860, both previous to and in connexion 

 with the great outburst of solar energy that occurred towards the 

 end of June in that year, I noticed a very marked monthly maximum 

 and minimum of solar spots ; and while there existed indications of 

 an intermittent action of the solar force, I was satisfied that the 

 maxima and minima I had frequently noticed were dependent on the 

 rotation of the Sun. 



Regarding each group of spots, single spots, if unattended by 

 smaller ones, or separate nuclei if they were sufficiently distinct to 

 warrant the appellation, as centres of energy, I laid down from time 

 to time curves of which the centres of energy were the ordinates. 



Taking the solar meridian turned directly towards the Earth at 

 noon of the 9th of July 1861 equal to 270°, and employing the 

 period of 27 d 7 h 10 m as that of the synodical rotation of the Sun, I 

 set off 27 abscissae, each being distinguished by a Roman numeral i. 



Phil. Mag. S. 4. Ts T o. 164. Suppl. Vol. 24. 2 P 



