ON THE TOTAL ECLIPSE OF THE SHN, MAY 28, 1900. 
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times and position angles of contact derived from the formulae given in the ‘ Nautical 
Almanac Circular,’ No. 17, were as follows :— 
Beginning of totality. May 28 4h. 12m. 51 As. G.M.T. 
End of totality. May 28 4h. 14m. 10'5s. 
Duration of totality, Im. 18'8s. 
Position angle of first contact, 87'’ 3'‘5 from N. towards VV. 
„ „ last „ 93° 47'-3 „ N. „ E. 
The experience of the Indian Eclipse of 1898 suggested that the duration of 
totality given was too long, and for the practical working during the eclipse tlie 
adopted time was 7 5 seconds, so that there would be no chance of spoiling the corona- 
graph plates by exposing them after totality. The face of the eclipse clock was 
graduated accordingly. 
The sun’s altitude at mid-totality was calculated to be 33° 23', and the amplitude 
2 ° 25' north of west. The apparent semi-diameter of the sun and moon were respec¬ 
tively 15' 48"'l and 16' 5"’9, and the relative motion per second 0"'447. At 
mid-totality the north point of the sun’s disc, direct view, was 57° 44' to the right 
of the vertex, and as the sun’s axis'was 17° west of the nortli point, the sun’s north 
pole was 74° 44' to the right of the vertex. The heliographic latitude of the centre 
of the sun’s disc being —0° 56', the direct view was as represented in the accompanying 
diagram; the points of contact with reference to the sun’s axis are also shown, 
and for 2nd and 3rd contacts they also represent very nearly the disposition Avitli 
regard to the vertex. 
Verbeco 
Fig. 2. Illustrating direction of sun’s axis at time of totality, and position angles of contacts. 
Time Arrangements. 
The arrangements for tiie time service were similar to those made for the Indian 
eclipse of 1898. Greenwicli time was ascertained by reference to the ship’s chrono- 
