 | Robert Gibson - 1811 - 580 ページ
...sum will be the log. sine of the true amplitude, to be reckoned from the east ia the morning, or the west in the afternoon, towards the north or south,...north or both south, their difference is the variation ; but it one be north and the other south, their sum is the variation ; and to know whether it be easterly... | |
 | Robert Gibson - 1814 - 558 ページ
...suai will be the log. sine of the true amplitude, to be reckoned from the east in the morning, or the west in the afternoon, towards the north or south,...declination. 2. Then if the true and magnetic amplitudes, be brfth north or both south, their difference is the variation ; but if one be north and the other south,... | |
 | Robert Gibson - 1832 - 290 ページ
...sum will be the log. sine of the true amplitude, to be reckoned from the east in the , morning or the west in the afternoon, towards the north or south,...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... | |
 | Robert Gibson - 1833 - 436 ページ
...variation of the compass by an amplitude. morning or the west in the afternoon, towards the north lor south. according to the declination. 2. Then if the...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... | |
 | John William Norie - 1840 - 184 ページ
...stand the sun's true amplitude, which is to be reckoned from the east in the morning, and from the west in the afternoon, towards the north or south, according to the declination. NOTE. When the minutes of the latitude or declination are nearly 30, or half a degree, the mean of... | |
 | Janet Taylor - 1842 - 592 ページ
...the logarithmic sine of the true amplitude, to be reckoned from the cast in the morning, or from the west in the afternoon, towards the north or south according to the declination. Now, if the true amplitude thus found, and the magnetic amplitude observed by the compass, he both... | |
 | Alexander Baharie - 1844 - 218 ページ
...azimuth. The true amplitude of a celestial object is reckoned from the east in the morning, and from the west in the afternoon,, towards the north or south, according to the declination. The true azimuth of a celestial object is reckoned from the south, if the observer be in north latitude,... | |
 | Basil Jackson - 1847 - 410 ページ
...degrees and minutes between the true E. or W. 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 ; but if one be north and the other south, their sum is the variation : and, to know whether it be... | |
 | John William Norie - 1852 - 844 ページ
...will be the log. sine of the true amplitude*, to be reckoned from the east in the morning, or from the west in the afternoon, towards the 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... | |
 | Sir George Back, Royal Geographical Society (Great Britain) - 1878 - 120 ページ
...corrected for the time and place of 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 ; but if one be north and the other south, their sum is the variation; and to know whether it be easterly... | |
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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 towards... 