246 The Eclipse of Last December, [April, 



the matter occupying a large portion of them must be so 

 much more brilliantly illuminated. The obliteration of the 

 stars by the light of the sun cannot be more complete than 

 the obliteration of the light from the region e m by that 

 from the region beyond m, up to, and past s. 



The polariscopic observations, as I have mentioned, are 

 perplexing, and in some respects seem contradictory. They 

 seem, however, to establish these results, that (1) a con- 

 siderable proportion of the coronal light is reflected ; (2) that 



Fig. 10. 



Illustrating the main objection to Oudemann's Theory of the Coronal 



Radiation. 



all the reflection has not taken place in our own atmosphere ; 

 and (3) that it is not such as would result if the sun's light 

 were reflected from mere amorphous dust, but rather as 

 though the reflection took place from surfaces of a crystalline 

 nature.* 



And now to sum up — very briefly, for already I have ex- 

 ceeded my allotted space — how does our knowledge respecting 

 the corona now stand, and in what respects has it been 

 increased ? It will be gathered from what I have already 

 said that I attach no great weight to certain results which 

 have elsewhere been dwelt on as the most important fruits 

 of the expedition, — for this reason, simply that those results 

 had been obtained long before the expeditions set forth, and 



* The account of the eclipse would be incomplete without a reference to the 

 remarkable observations made by Sig. Diamilla Muller of the variations in 

 terrestrial magnetism during the eclipse. He says in the " Gazzetta Ufhciale 

 del Regno dTtalia," January 17 : — " On the 22nd December the needle followed 

 its usual course till the commencement of the eclipse. At that moment it 

 ought to have continued its usual motion from east to west. Instead of this, 

 soon after the first contact, its westerly motion stopped, and it retraced its 

 steps till it reached its minimum declination at 1 hr. 58 min. (Terranova mean 

 time) exa&ly at the instant of totality. From the moment of totality to that 

 of last contact, as the disc of the sun gradually reappeared, the ascending 

 motion towards the west began anew ; and at the end of the eclipse the decli- 

 nation needle had returned to the precise position which it had quitted at the 

 beginning of the phenomenon." This observation merits the most careful 

 study; but I have not here space to indicate the conclusions to which it would 

 seem to point. 



