PROFESSOR J. I!^ORMAN LOCKYER ON THE 
2 
to select a station on the south side of the Varanger Fjord. The final choice of a 
place for observation was to depend upon examinations of suitable sites near the 
central line of eclipse, which as a result of local inquiries seemed to show the 
greatest probability of a fine morning on August 9th. 
The Norwegian Government readily granted permission to land, and instructed the 
authorities at Yadsb to render assistance. 
The party consisted of Mr. Fowler, Dr. W. J. S. Lockyee, and myself. Being a 
delegate to the International Conference on Bibliography, I could not leave London 
before July 22nd. Mr. Fowler and Dr. Locky^ee, therefore, went on in advance, and 
joined H.M.S. “ Volage ” at Hammerfest on July 22nd. 
Objects of Expedition. 
The success Avbich attended the use of the large scale prismatic camera during the 
total eclipse of 1893, indicated that spectroscopes of this form were the most 
important instruments which could be employed on an eclipsed sun. In the report 
on the results obtained in 1893"^ I have given a full account of the appearances 
shown on photographs taken with prismatic cameras, and have indicated the special 
points to be considered in interpreting them. It may be remarked, however, that 
among the special services rendered by the instrument are (1) the separation of the 
true coronal spectrum from the apparent one produced by reflected chromospheric 
light when a slit spectroscope is employed ; (2) localisation of the different radiations, 
so that we get a complete separation of coronal from chromospheric light, and 
information relating to the distribution of any particular radiation ; (3) the special 
facilities for photographing the phenomena in the loAver parts of the sun’s atmosphere, 
in the region of the so-called “ reversing layer.” 
Profiting by previous experience, prismatic cameras of the highest available power 
formed the chief part of the instrumental equipment. These were the 6-inch pris¬ 
matic camera employed in Africa in 1893, and a 9-inch which had recently been 
purchased for the Solar Physics Observatory. The work of each of these instru¬ 
ments was arranged to supplement that of the other in as many particulars as 
possible. 
As long ago as 1871 I had occasion to lay stress upon the importance of securing 
a record of the integrated spectrum of the light proceeding from every part of the 
eclipsed sun. The use of an integrating spectroscope is now more necessary than 
ever, for the reason that the prismatic cameras define what part of the total 
light proceeds from the chromosphere and prominences, so that a simple subtraction 
gives us the spectrum of the corona. A large spectroscope, which will be described 
later, was accordijigly prepared as an integrating spectroscope for use during the 
eclipse. 
‘ Phil. Trans.,’ A, 1896, vol. 187, pp. .151-618. 
