The Norwegian Aurora Polaris Expedition 1902-1903 Volume 1, PT. 1
This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1908 edition. Excerpt: ...in all these respects. Surprising similarity is followed in the course of a few minutes by a complete difference or a decided contrast; a great deflection in one curve answers to a scarcely perceptible jag or bend in the other, while soon after in the one calm ensues, and in the other the liveliest motion. "These well.known properties of magnetic storms, as especially the longer and more intense disturbances have aptly been called, point unmistakably to prevailing local occurrences as the likeliest cause of these phenomena--occurrences of varying strength and extent, which, appearing now here, now there, perhaps also simultaneously at different places, probably exert a magnetic influence over the whole earth at the same moment, and attain an intense influence, but for the most part only over a more or less limited area." This characterisation of the perturbation-conditions during great magnetic storms will do sufficiently well as far as the arctic regions are concerned. As regards lower latitudes, on the other hand, our impression of the conditions is very often as nearly as possible the contrary. There, at any rate during the great storms, the circumstance that attracts most attention is the similarity that the perturbation presents at the various places. As a rule, for instance, the curve for the entire district, Stonyhurst to Pola and Wilhelmshaven to San Fernando, exhibits in the main the same form. The conditions at Tiflis also, often constitute a transition form to those at Dehra Dun. The difference in the forms of curve often only depends upon a gradual turning of the field. In conformity with this, our view of the great magnetic storms will be quite a different one, since we assume that the storm is often only of a local...
- Paperback | 102 pages
- 189 x 246 x 5mm | 195g
- 13 Sep 2013
- Illustrations, black and white