Page:Popular Science Monthly Volume 79.djvu/202

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198
THE POPULAR SCIENCE MONTHLY

and was very remarkable. Its drift across the country was noted by many observers. It was eight miles in length at first and drifted at the rate of 122 miles per hour at a height of 54 miles, and it was watched by observers in different cities for thirty minutes. It finally assumed a globular form, and at one time was calculated to be four miles in diameter, thus covering a space of at least ten or fifteen cubic miles!

A meteor leaving another long-enduring train appeared over the south of England at 7:30 p.m., February 22, 1909. Mr. W. F. Denning considers this meteor with its train the most remarkable one in modern times. The train gradually increased in brilliance and twisted about, assuming grotesque shapes. A part of it drifted to the northwest at a velocity of 80 miles per hour and remained plainly visible until 9:30 or 10 o'clock. Another portion of the phosphorescent cloud drifted at a very much greater speed; according to the calculations of Mr. Denning, the best authority on meteors, the rate of 300 miles per hour was observed! This velocity is more than double that of any other drifting train hitherto observed, and indeed shows an extraordinary movement of the atmosphere. The train may have been illuminated for a time by sunlight on account of its appearance so early in the evening. This is the longest instance of visibility of a train seen at night. The record duration of a train illuminated by reflected light of the sun is that of the smoke train left by the meteor which exploded over Madrid, Spain, on the morning of February 10, 1896, and which was visible for five and one half hours as a reddish cloud.

Meteor Trains Observed in the United States in 1901

Professor E. E. Barnard, of the Yerkes Observatory, who has made a number of interesting observations of meteor trains reported two that he observed early on the morning of November 15, 1901. The first was formed by a brilliant meteor which radiated from the constellation Leo. This train was greenish-white in color, about 5° long, or a distance equal to ten times the diameter of the moon. It remained visible from 2:54 to 3:40 a.m. Another, which is shown by an illustration, was first seen at 3:10 a.m. and was conspicuous until 3:40 a.m., when it was obscured by clouds. Its color was greenish-white also. This train gradually expanded until it covered 20 or 25 degrees of the sky, forming two tails and appearing much in the likeness of a comet. Another train shown by three sketches made by the observer was seen by Mr. E. M. Dole, November 14, 1901, about 5:09 a.m. at Jamaica Plain, Mass. The large size of the train is made evident by comparison with the familiar stars of Ursa Major, "The Big Dipper," which appear in the drawing. The train was greenish in color, gradually turning to white. It was also seen at the observatory of Brown University, Providence, R. I. This cosmic cloud, according to an estimation which cannot be far