 ... that is, in the plane which passes through the north and south magnetic poles. There are places where the magnetic meridian coincides with the terrestrial meridian ; in these a magnetic needle freely suspended, points to the true north, but if it...  On the Connexion of the Physical Sciences - Page 310by Mary Somerville - 1834 - 458 pagesFull view - About this book
 | Thomas Liddell Ainsley - 1880 - 482 pages
...the Variation of the Compaes. Imaginary lines on the surface of the earth, passing through all points where the needle points due north and south, are called Lines of no Variation, and lines passing through all points where the needle is deflected from the geographical meridian are called... | |
 | John Bradley Harbord - 1883 - 472 pages
...makes with the geographical meridian. Imaginary lines on the earth's surface passing through all points where the needle points due north and south, are called Lines of no Variation ; and lines passing through all points where the needle is deflected from the geographical meridian by an... | |
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