390 
SIR NORMAN LOCKYER AND OTHERS 
The instrument was mounted equatorially, and provided with an excellent driving 
clock. 
One photograph was taken with an instantaneous exposure at call of 70 from the 
timekeeper at the eclipse clock, and another from, as soon as the plate could be 
changed, to the call of 5, the exposure thus being about 60 seconds. Sandell triple- 
coated plates, 6 inches square, were employed in each case. 
(3.) The Graham coronagraph. Aperture 3 inches, focal length 20 inches. Assis¬ 
tant Engineer W. J. S. Perkins in charge. 
This instrument, together with the small ccelostat with vTich it was used, was 
loaned to the expedition by the Marquis of Graham. Only one exposure was 
made during totality—from the call of 70 to that of 5 from the eclipse clock—the 
exposure being aliout 60 seconds. Seven additional plates were exjiosed at half- 
minute intervals after totality, with the view of ascertaining how long the corona 
could be jihotographed after the sun had reappeared. Sandell plates, 3 inches 
square, were employed throughout. 
The exposures were successfully made in each case. 
Discs. 
Six discs for cutting out the bright light of the inner corona were erected, with 
the view of enabling the observers to detect the long extensions if there should 
be any. 
The following are particulars relating to the observations :— 
Sun’s altitude at mid-totality . . 
,, azimuth ,, ,, 
,, semi-diameter 15' 48''‘12. . 
Disc to cover S' round sun 
6 ' 
? ? 9 ? ^ 3 J 3 5 • • 
= 33i°. 
= N. 871° W. 
= 948"T2 Piadius 
=: 1128"T2 „ 
= 1308"T2 „ 
Exam])le. 
Disc No. 1, 6 -inch diameter— 
Distance from eye to cover 6 ' round sun . . = 39|- feet. 
Height above eye . . . . . . . . =22 feet 1 inch. 
Height above ground . . . . . . . . =26 feet. 
With reference to this branch of work, the following statement has been drawn up 
by Mr. J. A. Daniels, Gunner, R.N., who superintended the erection of the discs and 
eye-pieces, adjustments for azimuth and altitude being made by Lieutenant 
Andrews :—• 
“ The eclipse camp being on perfectly level ground, the six discs were fixed up on 
poles, rough spars from the ship lieing found suitable for this purpose. 
“ Owing to the loose sandy nature of the soil, it was found necessary to secure the 
