ON THE TOTAL ECLIPSE OF THE SUN, MAY 28, 1900. 
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heels of the poles in casks sunk in the ground, stones and turf being rammed down 
tight round them, the lieads being further secured by four rope stays, taken to pegs 
about 4 feet long driven into the ground. 
“ On the poles being set up, steps were fixed for convenience of mounting the poles 
to place and adjust discs. 
“The discs, which were made of wood, varied from 6 to 2 inches in diameter; they 
were painted a dead black, and were fixed at the ends of brass rods which projected 
at right angles to the poles. These brass rods were placed at correct height, allow¬ 
ance being made for height of eye. The rods were further secured and stayed to the 
pole by twine. They were then turned to an angle of 33|-° with the vertical, so as to 
place them at right angles to the line of observation. The correct angle of each disc 
was obtained by fixing a plumb line to the edge of a triangle which was ruled with 
pencil at the angle of 33^°. 
“ Eye-pieces. —-These in each case consisted of a small piece of sheet brass, with a 
hole pierced in it of about inch in diameter, which was fitted on the front face of 
a framework made sufficiently large for a seat for the observer to be placed inside it. 
The front face was carefully adjusted so as to be parallel to its corresponding disc, 
and the eye-piece arranged so as to have a movement on its frame, both in altitude 
and azimuth, for purposes of final adjustment. The correct position of these frames 
and eye-pieces required a good deal of very careful observation to arrive at. Compass, 
spirit level, and a large wooden triangle having an angle of 33|-° were used for this 
purpose.” 
Arrangement of Observers. — The six discs were each worked by three persons, 
who were told off as Nos. 1, 2, and 3. Their duties were as follows - 
No. 1 to observe the corona and describe to No. 2. 
No. 2 to write down the description given by No. 1. 
No. 3 to blindfold No. 1, and to lead him to the eye-piece at the correct time, and 
to repeat time calls from the eclipse clock. 
The routine carried out was as follows :— 
10 minutes before totality (bugle “Alert”)— 
Blindfold No. 1 ; then Nos. 1 and 2 turn their backs to the sun. No. 3 takes the 
place to be occupied by No. 1, and keeps eye-piece adjusted. 
16 seconds before totality (bugle 2 G’s)— 
No. 1 is led to position at eye-piece by No. 3. 
5 seconds before totality (bugle 1 G). 
Order ^‘Go” at totality, and 75 seconds is called from eclipse clock and repeated 
by No. 3. At 65 being called from clock the bandage was removed from the eyes 
of No. 1, who looks through eye-piece and describes to No. 2 what he can see of 
the corona. No. 3 continues to repeat the time called from the eclipse clock, and 
makes a rough sketch of the corona to assist No. 1, who makes his sketch from 
his description given to No. 2 when totality is over. 
