1808.] 



Solar Eclipse uj 1808. 



1:23 



of the bands at that point, I changed eyepieces applying that of 4 1 power. 

 With this eyepiece the first clear instant showed the bands much brighter 

 than before, coloured, and as tangents to the limb at a point about 200° 

 from the vertex; but before I could determine anything further a cloud 

 shut out the view, and a few seconds later a sudden rush of light told that 

 the totality was over, though it Avas difficult to believe that five minutes had 

 flown by since its commencement. 



"I experienced a strong feeling of disappointment and want of success ; 

 the only points on which I can speak with any confidence being as fol- 

 lows : — (1) When using the double-image prism, the strong difference of 

 colour of the two images of the corona, and the absence of such difference 

 in the case of the most prominent red flame. (2) With the * Savart's po- 

 lariscope' the bands from the corona were decided; with a low power they 

 were wanting in intensity and colour ; excepting alternate black and white, 

 making it difficult to specify the nature of the centre ; and their position 

 was at right angles to the limb, extending over about 30° of the circumfe- 

 rence. When the polariscope was turned the bands travelled bodily round 

 the limb without other change in position or arrangement, as if indeed they 

 were revolving round the centre of the sun as an axis. With a higher 

 power, when a smaller portion of the corona was embraced, the bands were 

 brighter, coloured, and seen in a different position, viz. tangents to the 

 limb. 



"The appearance observed with a low pow r er seems exactly what might 

 be expected, supposing the bands to be brightest at every point when at 

 right angles to the limb, in which case the bands growing into brightness at 

 each succeeding point of the limb would distract attention from those fading 

 away at the points passed over as the analyzer revolved. 



'* After totality was over the clouds cleared away somewhat, and I 

 watched the eclipse till its conclusion, noting the times of emersion of the 

 spots and of last contact. 



" A light shower fell at 9.30. 



" During totality several stars and planets were seen by those who were 

 with me ; and a fowl which 1 had placed near me, out of curiosity, was ob- 

 served to compose itself to sleep. It was at no time so dark as I had ex- 

 pected : after the total phase had commenced I read the chronometer and 

 wrote notes in pencil without difficulty ; and the light of a bull's-eye lantern 

 when thrown on my paper appeared somewhat dull. 



" The brilliance of the light of the corona when it burst out through the 

 openings in the clouds astonished me. Also the very gradual decrease of 

 light before totality, and the wonderful flood of light which followed the 

 instant of the sun's reappearance (though behind a cloud) were very 

 striking. 



" I was too much occupied in watching the position of the sun, so as not 

 to lose an instant of the precious intervals uf clearness, to see much of the 

 general effect. I had no opportunity of using the hand spectroscope. 



