TOTAL ECLIPSE OF THE SUN, JANUAEY 22, 1898. 
153 
Plate 4. Plan of Fort Viziadrug, showing positions of instruments. 
Plate 5. Four photographs of the corona. 
Plate 6. Series of ten spectra taken near the beginning of totality with the 6-inch prismatic camera. 
Plate 7. Four spectra taken near mid-eclipse. 
Plate 8. Series of ten spectra taken near the beginning of totality with the 9-inch prismatic camera. 
Part I. —General Arrangements. 
By Sir Norman Locky]']r, F.R.S. 
Objects of the Expedition. 
For the expedition to Kio Island in 189G I had arranged an extensive programme of 
observations which unfortunately could not be completely carried out on account of 
had weather,and I did not find it necessary to materially modify this programme 
for the expedition of 1898. In view of the la.rge number of observers which was 
expected to be available in 1898, as in 189G, the observations proposed included 
records of nearly all the phenomena of a total eclipse, in addition to spectroscopic 
researches. 
Three associated series of spectroscopic observations were provided for : 
(1.) Prismatic cameras, to give records of the jdienomena with a larger dispersion 
than any previously employed. The special features of this form of spectroscope, 
and the important points to be considered in the interpretation of the photographic 
records which they give, were described in the Report on the Eclipse of 1893.1 
(2.) An integrating spectroscope of large dimensions to attem])t to get stronger 
photographic indications of the coronal radiations, by utilising the whole area of the 
corona, which the prismatic camera cannot do. 
(3.) A grating spectroscope, in conjunction with a telescope of large aperture and 
short focus, for eye observations of the inner corona. The spectrum of the chromo¬ 
sphere, as photographed in 1893 and 189G, showed that the Fraunhofer lines were not 
completely represented, and it seemed likely that the missing lines would be found 
above the chromospheric layer photographed, and associated with the coronal layers, 
of which we had photographed only a few of the brightest radiations. I certainly 
saw some of them in Egypt in 1882,| and it was accordingly decided to attempt to 
fill the blank in the photographic record l)y visual observations. 
The present Report deals with all the observations except those made with the 
prismatic cameras, in which case the work of reducing the photographs is very heavy 
and will not be completed for some time. 
* ‘ Phil. Tnius.,’ A, vol. 190 (1897), p. 2. 
t ‘ Phil. Trans.,’ A, a'oI. 187 (1896), pp. 551-618. 
I ‘ Eoy. Soc. Proc.,’ vol. 34, p. 297. 
VOL. CXCVII.—A. 
X 
