 | John William Norie - 1840 - 184 pages
...the magnetic amplitude by a compass, if they be both north, or both south, their difference will be the variation ; but if one be north, and the other south, their sum will be the variation ; and to know whether it be easterly or westerly, suppose the observer looking... | |
 | Alexander Baharie - 1844 - 218 pages
...Rule. — If the true and magnetic amplitudes be both north or both south, their difference will be the variation ; but if one be north and the other south, their sum will be the variation. Then, if the true amplitude be to the right of the magnetic, the variation will... | |
 | Nathaniel Bowditch - 1846 - 854 pages
...otherivi.se west. If the observed anil true amplitudes be both nnrih or both south, their difference mill be the variation ; but if one be north and the other south, their sum unit be the variation. If tlie true und observed azimuths be both east or both west, their difference... | |
 | Basil Jackson - Military reconnaissance - 1847 - 410 pages
...and the magnetic is the variation of the needle. Observe, if the true and magnetic amplitudes be both north or both south, their difference is the variation...north and the other south, their sum is the variation : and, to know whether it be easterly or westerly, suppose the observer looking towards that point... | |
 | John William Norie - Nautical astronomy - 1852 - 844 pages
...north or south, according to the declination. 3. Then, if the true and magnetic amplitudes be both north, or both south, their difference is the variation...north, and the other south, their sum is the variation : and to know whether it be easterly or westerly, suppose the observer looking towards that point of... | |
 | William Somerville Orr - Science - 1856 - 622 pages
...south. If the true amplitude, and that by compass, be both north or both south, their difference will be the variation, but if one be north and the other south, their sum will be the variation, easterly when the true amplitude is to the right, and westerly whin it is to... | |
 | Royal geographical society - 1883 - 328 pages
...observation. Their sum will be the log-sine of the true amplitude. If the true and magnetic amplitudes be both north or both south, their difference is the variation...north and the other south, their sum is the variation; and to know whether it be easterly or westerly, suppose the observer looking towards that point of... | |
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Then if the true and magnetic amplitudes, be both north or both south, their difference is the variation ; but if one be north and the other south, their sum is the variation ; and to know whether it be easterly or westerly, suppose the observer looking... 
