1904 - 5 .] On Prof. Seeliger’s Theory of Temporary Stars. 537 
in this case a broad bright line with two maxima, the centre of 
which lies at the normal position, and a hazy absorption-band 
on the violet side of the bright band. We notice that the 
assumption of a more energetic expansion at once explains why 
the bright Perseus-lines should have been found in normal positions, 
contrary to what had been seen in the former fainter Novae, 
where these bands were displaced towards the red. 
The fact that the bright bands in Nova Persei were not dis- 
A 
placed renders it difficult, on the other hand, to accept either the 
high-pressure or the abnormal-refraction theory. According to 
the former, we must expect, under all circumstances, displace- 
ment of the bright bands towards the red, while the absorption - 
bands should appear in normal positions. The observations show 
that in Nova Persei just the opposite phenomenon occurred. The 
a priori improbable assumption which might save the theory, viz. , 
that the star may have possessed an enormous proper motion towards 
us, is clearly contradicted by other observed facts. In the case of 
the refraction theory the same difficulty is experienced, even in 
