. Narrative of a journey to the shores of the Polar Sea, in the years 1819, 20, 21, and 22 [microform]. Scientific expeditions; Expéditions scientifiques. No. III.] LIEUTENANT HOOD ON THE AURORA. 595 The above diurnal variations were obtained by one of Kater's Compasses, which may be read within a minute by the reflecting microscope. It was placed on a shelf in a room of the Expedition-house, at Fort Enterprise, and close to a parchment window, which admitted the air, by several holes. No ferruginous matter was near enough to affect it; but it was twice accidentally moved ; and although the e
. Narrative of a journey to the shores of the Polar Sea, in the years 1819, 20, 21, and 22 [microform]. Scientific expeditions; Expéditions scientifiques. No. III.] LIEUTENANT HOOD ON THE AURORA. 595 The above diurnal variations were obtained by one of Kater's Compasses, which may be read within a minute by the reflecting microscope. It was placed on a shelf in a room of the Expedition-house, at Fort Enterprise, and close to a parchment window, which admitted the air, by several holes. No ferruginous matter was near enough to affect it; but it was twice accidentally moved ; and although the extent of the error thereby occasioned, was ascer- tained by comparison with Mr. Franklin's observations, and those of the pre- ceding days, yet their connexion is not to be fully depended on, so as to de- rive from them the monthly variations. However, the intermediate periods will serve to show the variation for particular days, and also the amount of aberration caused by the Aurora. i 1 1 '' â " 1 i ..-:hl;i 1 ?,' , 1 lo ?⢠14 15 0 , 55 f 44 1 33 1 34 i 20 49 :: 31 20 13 1& , 55 > 34 A diurnal variation evidently exists ; the maximum of which is at 9h. a. m. and the minimum, at 3 or 4h. p. m. The irregularities of the needle may be at- tributed to the Aurora; because the appearance of that meteor has been so much more frequent here than at Cumberland-House, where the needle was not often distuibed. Some other opinions were inserted in this part of Mr. Hood's journal; but as they are detailed more at length in his preceding remarks on the Aurora Borealis at Fort Enterprise, they are omitted S^-:.,-: I li ' 4S. 4 G 2 *. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Franklin, John, Sir, 1786-1847. London : J. Murray
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Keywords: ., bookcentury1800, booksubjectscientificexpeditions, bookyear1823
