1893.] on tie Becent Solar Eclipse. 145 



photometer, the light from the standard glow-lamp being varied by- 

 introducing a variable amount of resistance into the current and 

 measuring the current strength at the moment of comparison. 



In order to ascertain the total intensity of the coronal light 

 Mr. Forbes employed a similar contrivance, his screen, however, 

 having only one large translucent spot or disc, as in the ordinary 

 Bunsen photometer. Concurrently with these observations it was 

 arranged that the photographic intensity of the coronal light, as dis- 

 tinct from the visual intensity, should also be measured by a method 

 devised by Captain Abney, which consists in impressing standard 

 intensity scales along the edges of the photographic plates to be 

 exposed in the coronagraph, these being developed at the same time 

 as the coronal pictures. The photographic plates to be used in the 

 split spectroscope were also provided, in like manner, with standard 

 scales, with a view of measuring the comparative luminosity of dif- 

 ferent portions of the coronal spectrum, a point which has an im- 

 portant bearing on the question of the possibility of photographing 

 the corona in ordinary sunlight. 



On the day preceding that of the eclipse the French gunboat 

 Brandon came up the river, bringing with her the Governor of 

 Senegal. His Excellency M. de la Mothe, together with the adminis- 

 trator of the district, M. Allys, to whom the expedition is indebted 

 for many courtesies, paid a visit to the English camp at Fundium 

 and witnessed the final rehearsal of our operations. They arranged 

 for a guard to protect the enclosure during the time of the eclipse, 

 and gave orders that all chanting, screaming, or beating of tom-toms 

 in the village was to be forbidden. 



On Sunday, the 16th, the day of the eclipse, although the morn- 

 ing was bright and clear, the effects of the comparatively moist winds 

 from the sea were to be seen in the changed colour of the sky and 

 the prevalence of thin haze. Still the sky was almost cloudless, 

 save for a few thin wispy cirri, which floated almost motionless 

 near the horizon. A gentle air from the west made scarce a 

 ripple on the yellow waters of the Salum. As the day advanced, 

 the sky became even lighter in colour, and there was a perceptible 

 haze in the neighbourhood of the sun ; the wind almost died 

 away, and everything betokened that we should have to face — as 

 indeed we fervently hoped might be the case — the pitiless glare of 

 that fiercest of all suns — the African sun at noon. At 12.30 our 

 party went ashore, the huts were uncovered, the equatorials adjusted, 

 clocks wound, and the instruments set running on the sun. Shortly 

 before 2 p.m. the officers and men from the Alecto, bringing their lan- 

 terns, came to the camp and took up their several positions. As the 

 light waned there was a distinct feeling of chilliness in the air, and 

 the wind suddenly rose in short sharp gusts. The few natives who 

 had congregated round the stockade began to show signs of trepida- 

 tion, but no sound of distress or fear was heard save the plaintive 



Vol. XIV. (No. 87.) l 



