It is noteworthy that several careful observers of the corona in 1842 believed that they could recognise motion in the coronal rays. Francis Baily compared the appearance of the corona to the flickering light of a gas illumination. O. Struve also was much struck by the appearance of violent agitation in the light of the ring. It seems probable that the appearance was due to movements in that part of our atmosphere through which the corona was observed. The extent of the corona was variously estimated by different observers. Petit, at Montpelier, assigned to it a breadth corresponding to a height of about 200,000 miles; Baily a height of about 500,000 miles; and O. Struve a height of more than 800,000 miles. The last-named observer also recognised luminous expansions extending fully four degrees (corresponding to nearly seven million miles) from the sun. Picozzi, at Milan, noticed two jets of light, which were seen also by observers in France. Rays also were seen by Mauvais at Perpignan, and by Baily at Paria. But Airy, observing the corona from the Superga, could see no radiation; he says 'although a slight radiation might have been perceptible, it was not sufficiently intense to affect in a sensible degree the annular structure by which the luminous appearance was plainly distinguished.' These varieties in the aspect of the corona were doubtless due to varieties in the condition of the atmosphere through which the corona was seen. Now it cannot be questioned that, so far as extension is concerned, the corona seen in 1842 was one which, if the theory we are considering were sound, we should expect to see near the time of maximum rather than of minimum solar disturbance. On the other hand, in brightness the corona of 1842 resembled, if it did not surpass, that of July 1878. 'I had imagined,' says Baily, 'that the corona, as to its brilliant or luminous appearance, would not be greater than that faint crepuscular light which sometimes takes place (_sic_) in a summer evening, and that it would encircle the moon like a ring. I was therefore somewhat surprised and astonished at the splendid scene which now so suddenly burst upon my view.' The light of the corona was so bright, O. Struve states, that the naked eye could scarcely endure it; 'many could not believe, indeed, that the eclipse was total, so strongly did the corona's light resemble direct sunlight.' Thus while as to extent the corona in 1842 presented the appearance to be expected at the time of maximum solar disturbance, if our theory is sound, its brightness was that corresponding to a time of minimum disturbance. Its structure corresponded with the former condition. The light of the corona was not uniform, nor merely marked by radiations, but in several places interlacing lines of light could be seen. Arago, at Perpignan, observed with the unaided eye a region of the corona where the structure was as of intertwined jets giving an appearance resembling a hank of thread in disorder.