354 C. A. Young—=Spectroscopic Notes. 
to verify the ep ebdcrs except for a moment during the 
e 
these special rays, and exclusion of extraneous light T have no 
further difficulty with the observation. e a jam 
employed has collimator and view-telescope each of 14 inches 
aperture, and about thirteen inches focal length, and a a 
lum-metal Rutherfurd grating with 17,300 lines to the inch. 
A shade of cobalt blue glass greatly aids the observation. 
The solar image is 1} ‘iohen 3 in diameter. 
In the spectrum of the chromosphere, H and K are both 
always reversed. I have never failed to see them both when 
circumstances were bite that h, the nearest of the hydrogen 
lines, could be se 
to some other substance shan that which produces H an 
a substance prominent in the esi ibe, tena but not acialiy 
so in the neighborhood of spots. In view of the recent obser- 
vations of Vogel, Draper and Baoan, i is natural to think 
that hydrogen is probably the element concerned. If so, it 
may be expected that H will be found doubled in the spectrum 
of a spot which reverses the hydrogen line h. I have not yet 
been able to test it in this way, as h is rarely seen reversed, 
though C and F occur pretty cently: (See, further, a note 
by the author in the miscellany beyond.) 
Ul. gag sip of lines in the Solar Spectrum gerssol are given 
he Maps as common to two or more subst 
For en purpose a spectroscope of high fires has been 
constructed by combining the grating mentioned above, which 
has about four square inches of ruled surface, with a collima- 
tor and observing telescope each of three inches aperture and 
about 42 inches focal length, using magnifying powers ranging 
from 50 to 200. The apparatus is arranged 8 on a W 
frame oer and when in use is strapped to the tube of es 
