Page:Proceedings of the Royal Society of London Vol 69.djvu/269

Rh ccelostats which were necessarily quite close to the ground. The position of the latter, in the open air and placed horizontally, would render them more exposed to the effect of ground currents than the two other telescopes would be, pointing upwards at an angle of 19 and within domes.

The darkness during totality to the observers out in the open air was not great, the general illumination being considerably greater than at the full Moon. Five observers, noting the twilight illumina- tion in the evening after the eclipse, considered it equal to that of mid- totality at the following local times :

h. m.

Mrs. Claxton 5 58P.M.

Mrs. Maunder 5 57

Mr. Claxton 5 58

Mr. Hall 5 58

Mr. Maunder 5 57

corresponding in the mean to 31 minutes after geometrical sunset, or to a position of the Sun, neglecting refraction, of 6 53' below the horizon.

But the observers in the equatorial and photoheliograph domes found it very dark during totality. A sudden gust of wind came from the N.E. at the moment of second contact and blew out the observer's candle in the equatorial dome. The recorder here, Mr. Olivier, found it quite impossible to read his chronometer or to write in the darkness, and hence Mr. Piggott's determination of the times of the second and third contacts were wholly lost.

Venns and Mercury were both very brilliant, side by side, some 5 below the Sun, whilst Jupiter and Saturn were prominent in the western sky. No search was made for other celestial objects.

Times of the Contacts. The following determinations were made of the times of the three last contacts. As already stated, the first con- tact was lost through cloud :

Observe! 1

T. F. Claxton.

E. W. Maunder.

A. Walter.

Capt. Robertso

Place

E. Alfred Obs.

R. Alfred Obs.

R. Alfred Obs

ss. " Ugina "

Photoheiiograph

Corona^raph.

Ifawbegin telesc

Navy telescope

Aperture

4 in.

4 in.

44 in.

2 in.

Chronometer .... Error of chrono-

Kullberg 3400. 1 0"4 f.

H. White 1424. 3 h 53 m 47"3 s.

Webster 925 2 m 58* s.

Observed times Second contact. Third contact. . Fourth contact True local times Second contact. Third contact. . Fourth contact

9 h 5 m 43-0 9 4 ' 42-6

3 57 52-2 4 1 25-1 5 10 55-1

7 51 395 . 7 55 12-4 9 4 42-4

7 h 48' n 43- 7 52 16

7 51 41 7 55 13

7 h 51 m 38- 7 55 12