712 
PROFESSOR J. N. LOCKYER ON RESULTS OBTAINED WITH THE 
use of this form of spectroscope are overcome. The large refracting angle of the 
prism employed (45°) obviously increases the value of the instrument for eclipse work. 
This instrument was placed at the disposal of the Eclipse Committee by the Solar 
Physics Committee, and was entrusted to Mr. Fowler, who took the photographs 
at the African station. 
It also seemed important that a series of similar photographs should be taken at 
another point on the line of totality, even though an equally efficient instrument 
were not available. A spectroscope belonging to the Astronomical Laboratory of the 
Royal College of Science was lent for the purpose by the Science and Art Depart¬ 
ment, and a siderostat used in conjunction with it was lent by the Royal Society. 
These instruments formed part of the equipment of the Brazilian expedition, and were 
placed in charge of Mr. Shackleton, Computer to the Solar Physics Committee. 
The stations chosen were Fundium, on the Salum River, West Africa, and Para 
Curu, Brazil. The weather was fortunately favourable at both places. 
Tlie preliminary reports of work done at the stations named, by Mr. Fowler 
and M)’. Shackleton respectively, are appended; the object of these being to indi¬ 
cate the kind of results obtained. The complete discussion of the results, which will 
occupy some time, will form the subject of a future communication. 
(1.) African Observations. 
The prismatic camera employed at the African station had an aperture of 6 inches, 
the refracting angle of the prism being 45°. Spectra photographed with this 
instrument are 2 inches long from F to K, and rings corresponding to the inner 
corona are about seven-eighths of an inch in diameter. 
As very little idea could be formed of the exposures required, a series of four 
different exposures was repeated three times during totality, a specially long one 
being given near mid-eclipse. 
A complete list of the photographs taken is given in the appended table. Column 1 
contains reference numbers to the photographic plates; column 2 the brand of plate 
employed ; column 3 the times of beginning and ending each exposure, as recorded 
by a deck-watch ; and column 4 the amounts of exposure, “ Inst.” indicating an 
exposure given as quickly as possible by hand. 
There is a little uncertainty as to the exact time of commencement of totality, 
but there is reason to believe that it occurred at about 2h. 23m. 53secs. by the 
watch. 
