Page:Science vol. 5.djvu/564

 SCIENCE.

��display of northern lights. A number of illus- trationa aie given ; lint in all cases they are reproduced from drawings, as, even with the most sensitive platfis, lie ulterlj' failed in getting any impression on a negative. lie holds the opinion that the fundamental phenomenon is a ring of liglit encircling the earth, as shown in fig. 2, and that all the vni-ious forms observed are due to modifications and imperfections in this ring. To the streamers he gives the posi- tion which a dipping-needle would take, and explains their apparent coming-together at the magnetic /enitli, as liiey do occasion^illv, as

��of 1883 to the Finnish polar station, Ti-ombolt takes occasion to criticise the artificial am which Professor Lemstriim succeeded in ting on the lop of a hill. He thinks the lij_ more or the nature of St. Elmo's lire than true aurora. He also takes esccplion to Lem- strom's determinations of the height.

Koutokaeiuu was the seat of a religious ex* citement among the Lapps, which finally cul- minated in 18^2 in the murder of the trader and sheriff of the place, the pastor's life being saved only by the timely advent of a (few nrmpd and sane Lapps from a neighboring vil*

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���due to pers[)ective. He believes in such cases that the observer is looking into a lube of rays. The geographical distrilmlion of the aurora is described, and the results of the various estimates of the height given, Troniholt's own measurements making the average height of the lower edge ol' a numlwr of auroral arches 70.2 miles. The connection of the aurora with the sun-si>ot periods is referred to, and a bi- yearly vaiiation in the phenomenon is made probable. The crackling sound aomctiines said to have been heard, Tromholt was led to con- aider imaginary. As regards the strength of the light emitted, he sajs that at times he was able to read print of the following size : —

Aurora borealis.

In the account of his journey in the spring

��lage. A somewhat similar excitement was io 1883 brewing at Hatta to the east of Kouto-

The most of Tromholt's trips over the oouik- try were made in re in deer- sleds, when the snow was bard, and were accomplished with few more than the usual mishaps of such travelling, although his St. Bernard dog. Rolf, did not prove a congenial companion for the deer. But the final journey, to Sodankyla, was made when the sun had already begun to melt tbe snow; and, on his return, Tromholt pictureiJ himself aa dragged through from one to twoj feet of water for a great pait of the way. laM the spring the land must resemldc one vaat ■ mud-puddle. Finally Tromholt returned to civilization, and took his voyage along the north const of Scandinavia.

Thanks to the cheap photo -engi-aving pro-

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