DETERMINATION OF DEFLECTION OF LICIIT RY THE SUN’S GRAVITATIONAL FIELD. 81 8 
climate is very moist, but not imliealthy. The vegetation is luxuriant, and the scenery 
is extremely beautiful. We arrived near the end of the rainy season, but the (jravana, 
a dry wind, set in about May 10, and from then onwards no rain fell except on the 
morning of the eclipse. 
We were advised that the prospects of clear sky at the end of May were not very 
good, but that the best chance was on the north and west of the island. After in- 
- specting two other sites on the property of the Sociedade d’Agricultura Colonial, we 
fixed on Ro^a Sundy, the headquarters of Sr. Carneiro’s chief plantation. We were 
Sr. Carneiro’s guests during our whole visit, and used freely his ample resources of 
labour and material at Sundy. We learnt later that he had postponed a visit to Europe 
in order to entertain us. We were also greatly indebted to his manager at Sundy, 
Sr. Atalaya, with whom we lived for five weeks ; his help and attention were 
invaluable. Mr. Wright and Mr. Lewis of the Cable Station kindly assisted us as 
interpreters when necessary. 
Sundy is situated in the north-west of the island overlooking the sea at a height of 
500 feet, and as far as possible from the cloud-gathering peaks. Our telescope was 
erected in a small walled enclosure adjoining the house, from which the ground sloped 
steeply down to the sea in the direction of the sun at eclipse. On the other side it was 
sheltered by a building. The approximate position was latitude 1° 40' N., longitude 
29m. 32s. E. 
28. The baggage was brouglit to Sundy on April 28 mainly by tram, but with a break 
of about a kilometre, where it had to be transported through the wood by native 
carriers. After a week spent on the preparations, we returned to S. Antonio for the 
week. May 6-13, as it was undesirable to unpack the mirror so early in the damp 
climate. On our return to Sundy the installation and adjustments were soon com¬ 
pleted, and the first check plates were taken on May 16. Meanwhile the gravana 
had begun, which, although there is no rain, is generally accompanied by increased 
cloud. There were, however, some days of clear sky, and the nights were usually 
clear. 
The coelostat was mounted on a stone pier built for the purpose. The clock weight 
fell into a pit below the clock deep enough to allow a run of 36 minutes without 
rewinding. Care was taken to use a particular part of the coelostat-sector, considered 
to be the most perfect, in photographing the eclipse and the check field. The telescojie 
(Oxford astrographic object-glass, see p. 295) rested on wooden V’s near the two 
ends, the V’s being supported on packing-cases ; the one at the breech-end could be 
moved laterally to allow of different declination settings, and was marked with an 
approximate declination scale. A series of exposures of one second was made on a 
bright star to test whether there was any shake of the telescope after inserting the 
plate : no shake was detected even when the exposure was made immediately ; but 
as a safeguard for the eclipse photographs a full second was allowed to elapse before 
beginning the exposure. The exposure was made by moving a cardboard screen 
