Page:Popular Science Monthly Volume 16.djvu/580

From Wikisource
Jump to navigation Jump to search
This page has been validated.
554
THE POPULAR SCIENCE MONTHLY.

CORRESPONDENCE.

INTERESTING LUMINOUS PHENOMENON.

Messrs. Editors.

A BEAUTIFUL and unusual phenomenon was observed here on the afternoon of the 13th instant. Between three and four o'clock, the western sky being partially covered with cirri, and obscured near the horizon by a dense haze, about thirty degrees horizontally north of the sun was seen a mock-sun of dazzling brilliancy. Extending from it above and below was a luminous haze, of too small an extent and too indefinite outline at its extremities to exhibit any curvature. The entire mass of light thus appeared to have an oblate form, very much elongated vertically, the brilliant mock-sun forming its nucleus. On its sun-ward side the colors of the solar spectrum were plainly visible. In the clear sky, directly over the true sun, and about half-way to the zenith, was an inverted arch of pale white light, of parabolic form, with its axis to the sun, its extremities, which faded off into the blue, being five or six degrees apart. Directly overhead was an arc of a circle, of

still fainter light, whose apparent radius was about ten degrees. No prismatic tints could be detected in either of these arcs. The situation of the objects described is roughly shown in the diagram. The sky to the south of the sun was so covered by cirro-strati as to obscure any parhelion that might otherwise have been visible there. A noticeable feature of the phenomenon was the distinctly parabolic form of the middle arc of light. Never having seen this particular feature described in accounts of similar phenomena, I would ask if it is a usual accompaniment of them, and at the same time would ask if any satisfactory explanation of the cause of parbelia and the accompanying circles, other than the partial explanations of Huygens and Fraunhofer, has yet been given?

On the morning following the appearance described, we had light flurries of snow, and afterward rain.

G. B. Seely.
Boston, December 15. 1879.

"THE AGE OF ICE."

Messrs. Editors.

I have been placed in a false position through your publication, without date, of my article bearing the above title in your October issue of the current year. I am accused, by a paper called the "St. Louis Globe-Democrat," of plagiarizing from Croll and Merriman. Permit me to state that the article was written in 1874, nearly six years ago, and read at the session for that year of the Kansas Academy of Science, as the archives of that body will testify. I think Croll's book was not at that time published. Geikie's, if published, had not yet reached us in Kansas; and Mr. Merriman did not write till a later period. I had seen nothing on the subject but St. Pierre's "Studies of Nature," and a fugitive fragment from Adhemar. I think my manuscript was handed in too late to be printed in the "Transactions" of the Academy for that year; but doubtless the record of its presentation in 1874 is on file. I left Kansas soon after, and had seen nothing of my article from that time till the day it appeared in the "Monthly." You will testify that it was published without my knowledge.

I should have sooner adverted to the matter, only that I hoped the article would remain in the oblivion to which its slender merits entitled it; but now that I am charged with plagiarizing from men who, though vastly superior in knowledge and research, really wrote after I did, I beg space for the above, or for some editorial statement of a corresponding character.

I am yours, very respectfully
H. B. Norton.
San José, California, December 22, 1879.

Mr. Norton's article, referred to above, was received by us November 2, 1874, and was never afterward in the hands of the