An exception is made for runways within the Northern Domestic Airspace of Canada; these are numbered relative to true north because proximity to the magnetic North Pole makes the magnetic declination large.
32.
Lindbergh also installed a newly developed Earth Inductor Compass made by the Pioneer Instrument Company which allowed him to more accurately navigate while taking account of the magnetic declination of the earth.
33.
"Arte de navegar " was a practical book in which Cort�s discussed, in a concise manner, navigation, cosmography and problems such as magnetic declination for which he hypothesised a Celestial magnetic pole.
34.
In 1820, three commissioners reported to Governor Charles Douglass Smith their calculations of magnetic declination and placed stone markers to this effect in a field cleared immediately north of the Prince Edward Battery.
35.
I found the word " isogonic " ( DCE : " corresponding to equal values of magnetic declination " ) in a fascinating article about an escapist sea voyage in Saturday Night magazine.
36.
This drift of 2.9 miles ( 4.7 km ) northward is generally thought to be due to the change in magnetic declination, which he did not correct his compass for as the survey progressed.
37.
In it, he wrote of use for a drydock to repair boats, the navigational magnetic compass, and the discovery of the concept of true north ( with magnetic declination towards the North Pole ).
38.
Magnetic declination should not be confused with "'magnetic inclination "', also known as magnetic dip, which is the angle that the Earth's magnetic field lines make with the downward side of the horizontal plane.
39.
Muslim astronomers and geographers were aware of magnetic declination by the 15th century, when the Egyptian astronomer'Abd al-' Aziz al-Wafa'i ( d . 1469 / 1471 ) measured it as 7 degrees from Cairo.
40.
Another major difference between the NDA and SDA is that magnetic declination is not used in the NDA . Because the magnetic north pole is in the NDA, magnetic declinations are very large; sometimes even 180?
