TOTAL ECLIPSE OF THE SUN, JANUARY 22, 1898. 
191 
observations are in accordance with those of 1882. Thus, at 7 minutes ])efore 
totality in 1882, in the region of' the iron quartette to which reference is frequently 
made, short lines were noted at 4924 and 4934, and at three minutes before totality 
only 4957 was added as a line of moderate length ; these may be supposed to have 
escaped my notice at the corresponding intervals from totality on account of tlieir 
shortness. At 2 minutes before totality in 1882 the same lines were observed with 
the addition of long and fainter lines of the other three members of the arc quartette 
at 4872, 4891, 4919, and a titanium line at 4933 ; with the exception of the titanium 
line, therefore, my observation of the arc quartette at 2 minutes to 1 minute before 
totality agrees, supposing that I was only able to see the longer lines. 
In the chromosphere as ordinarily observed, and as photographed with the 
jOTsmatic camera, the enhanced Fe lines 4924 and 5018, and the Ba line at 4934, are 
more easily visible than the arc quartette, and it thus results that the arc quartette as 
observed before totality by me in 1898 and by Sir Norman Lockyer in 1882, 
proceeds not from the chromosphere, hut from a region above it. 
In connection with the observations during totality, it must l)e remembered that 
when a slit spectroscojDe is employed, lines may appear in the coronal spectrum which 
belong only to the chromosphere and prominences, on account of the light being 
scattered by our atmosphere. 
The brightest chromospheric lines in the F-h region are those of iron at 4924 and 
5016, and the barium line at 4934. These were, no doubt, among the lines which I 
observed at the beginning of totality, and are the lines which I should have seen in 
the inner corona if the lines noted were due to glare. As I did not see these lines, it 
would appear that glare was ineffective except in the case of F and h, and that the 
lines which I saw between F and h really belong to the corona. Here, again, we have 
an indication that the region above the chromosphere shows cool lines of iron, and, in 
connection with other lines of inquiry, this points to a region above tbe chromosphere 
as the source of some of the Fraunhofer absorption. 
Part IV.— The Prismatic Cameras. 
By Sir Norman Lockyer, K.C.B., F.R.S. 
llie Instruments employed and Photoyraphs obtained. 
The Instruments employed. 
The success which attended the use of the prismatic cameras in the' eclipses 
of 1893* and 1896,t led me to attempt to obtain photographs on a still larger 
scale in the eclipse of 1898. Two instruments were employed on this occasion, 
* ‘Phil. Trans.,’ A, vol. 187 (1896), pp. 551-618. 
t ‘Phil. Trans.,’ A, vol. 189 (1897), pp. 259-263. 
