' J. C.F. Zillner on a new Spectroscope. 63 
practicability of measurements, the velocity of rotation in vari- 
ous heliographic latitudes would be determined, which would 
be of the greatest interest with reference to the opinions pro- 
nounced most recently on this point. 
_ But even without regard. to a quantitave determination of the 
phenomenon in question, by means of a proof of it only quali- 
tative, even a simple means would be found of separating all 
the lines which arise from absorption in the earth's atmosphere, 
from those which owe their origin to the solar atmosphere, since the 
‘a gee in question could evidently extend only to the 
atter. 
Another subject for the investigation of spectrum analysis ~ ~~ 
is the protuberances. As is well known, Lockyer and Jansse 
were the first who succeeded, independently of a total eclipse — i 
of the sun, in observing the spectra of these forms, which con- 
sist of three bright lines. 
At the present time it is the object of most earnest en- 
: ar to its 
irection. In this way the protuberance could be observed in 
igh which the protuberance passes from its base, will how- 
ever be eountlleduly weakened, eg os. mote to the length of 
the path passed over by the slit; in the rotating spectroscope 
especially, the brightness of the protuberance itself would be 
weakened from the center of rotation out to the edge, and con- 
sequently the observation of the natural relations of the bright- 
hess of the image would be frustra 
Oe ay ee 
ted, 
_ For this reason I have in view the introduction of another - 
