. Transactions of the Royal Society of Edinburgh . he minute of observation, at the minute, and25s after it; the three readings being a, &, and c, the mean is deduced from the formula — The mean thus obtained is corrected to the temperature of 26° Fahr., a constant quantity of 300*0 has been added to all the corrected N be the observed mean, and t be the observed temperature of the bifilar bar,the corrected means n, given pages 1 to 170, are obtained from the formula n = N + 300-0 + (7-26°) 1-90 1*90 being the temperature coefficient in scale divisions. The means f in parts of the who
. Transactions of the Royal Society of Edinburgh . he minute of observation, at the minute, and25s after it; the three readings being a, &, and c, the mean is deduced from the formula — The mean thus obtained is corrected to the temperature of 26° Fahr., a constant quantity of 300*0 has been added to all the corrected N be the observed mean, and t be the observed temperature of the bifilar bar,the corrected means n, given pages 1 to 170, are obtained from the formula n = N + 300-0 + (7-26°) 1-90 1*90 being the temperature coefficient in scale divisions. The means f in parts of the whole horizontal force given in the abstracts of re-sults, pages 355 to 373, are obtained by the formula f=(n- 500)0-0001400-000140 being the value of k for 1844. No correction has been applied for the effect of the balance magnet, which isconstant. Balance or Vertical Force Magnetometer. 46. The balance magnetometer was made by Robinson of London ; it is com-posed of a magnetic needle cfc, 12 inches long, about |- inch broad, and about i kr. inch thick, with knife-edged axle /, which rests upon agate planes; brass rings c c areattached to the extremities of the needle, each ring carrying a cross of spider threads. Balance or Vertical Force Magnetometer. xxxv The needle is placed at right angles to the plane of the magnetic meridian, it is ac-curately adjusted to horizontality by a screw e which balances the needle, anotherscrew d working vertically, regulates its sensibility. The apparatus, and a ther-mometer h which gives the temperature of the needle, is covered by a rectangularbox k having glazed openings on both sides opposite the spider crosses; those on oneside allowing light to be thrown on the crosses from two small mirrors, (one of whichI is indicated in the figure); those on the other, for viewing them and determiningtheir position, which is done accurately by the microscopes b b carrying micrometers;the micrometer heads a a are divided into 50 divisions. The suppor
Size: 2023px × 1236px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorroyalsoc, bookcentury1800, bookdecade1840, bookyear1848
