Page:Popular Science Monthly Volume 1.djvu/35

Rh in those distant regions. It was marked with radial streaks of great brilliancy, separated by relatively dark furrows, and extending all round the upper and lower parts of the moon's circumference, but less conspicuous (or altogether wanting—the account is not very clear on this point) at the sides. This observation is of great interest, because the upper and lower parts of the sun's circumference at the moment of observation corresponded to the sun's equatorial regions, while the sides corresponded to the position of the solar poles. Mr. Lockyer's account thus seems to support a theory lately urged, according to which the corona is caused by radial emanations chiefly from the neighborhood of the solar equator. It is clear, however, from the rifts (especially as shown in the figure), that such emanations cannot be continuous, but must take place locally, and, as it were, fitfully.

But the most important account which has yet reached Europe is that contained in a letter from M. Janssen, the eminent spectroscopist, to M. Faye, the president of the French Academy of Sciences. It should be noted, in the first place, that in a letter to the secretary of the Academy Janssen says: "I have just observed the eclipse, only a few moments ago, with an admirable sky; and, while still under the emotion occasioned by the splendid phenomenon which I have but now witnessed, I send you a few lines by the Bombay Courier. The result of my observations at Sholoor indicates, without any doubt, the solar region of the corona and the existence of material substances (matières) outside the sierra." Then follows his letter to the president, which runs thus: "I have seen the corona as I could not in 1868, when I gave myself wholly to the prominences. Nothing could be more beautiful or more brilliant; and there were definite forms which exclude all possibility of an origin in our own atmosphere." He proceeds to describe the coronal spectrum, confirming the American observations—with one notable exception: he recognized the solar dark lines in the spectrum of the corona, a proof that no inconsiderable portion of its light is reflected sunlight. Then he draws his letter to a conclusion with these decisive words: "I conceive that the question whether the corona is due to our own atmosphere is disposed of (tranchée), and we have before us in perspective the study of the regions lying outside the sun, which must needs be most interesting and fruitful." I could wish that the same opinion had been received when it was advocated twenty-two months ago in almost the same words.—Cassell's Magazine.