The Theory of Temporary Stars. 

 Table II. — Bright Bands. 



From these figures we see that the dark bands were at first 

 strongly shifted towards the violet, regaining their normal posi- 

 tions about the beginning of April. The bright lines, too, were 

 at first displaced towards the violet (though less than the dai'k 

 ones) but by the middle of March this was exchanged for a much 

 smaller displacement towards the red, the lines returning to their 

 normal positions at about the same time as the dark ones. In 

 the April photographs, therefore, the characteristic paired lines 

 are no longer seen, being replaced by broad bright bands in 

 the normal positions, upon which broad hazy absorptions are 

 mesially superposed. 



The gaps in the Lick series of photographs are bridged by 

 those taken at South Kensington, as well as at the Yerkes^ and 

 Stonyhurst- observatories. These agree with the Lick photo- 

 graphs in showing that early in March the bright lines were 

 displaced towards the red ; while the South Kensington plates 

 show that on 26th February^ the displacement either way — • 

 if it existed — must have been small. On the other hand, the 

 Stonyhurst observations tend to show — in opposition to the 

 Lick observations — that the bright-line displacements remained 

 unchanged from 3rd March to 26th April ; it is, however, to 

 be noted that Father Sidgreaves' method of comparison is much 

 better suited to differential measurements than to absolute 



1 Ap. J., xiii., pp. 173, 238. 



2 M. N., Ixii., p. 137. 



3 It must not be forgotten that South Kensington is more than ten hours ahead of the 

 Lick Observatory in longitude ; a fact of fundamental importance where possibly rapid 

 changes are concerned. 



