Put the compass in different corners of the same room, but the north-south direction is very different. Why?

When the compass is placed in different areas and corners, different environments will affect the deviation of the compass. Another reason is that the magnetic declination of the compass does not mean due south.

Geomagnetic declination of place names

Mohe 1 1 00'

Qiqihar 9 54'

Harbin 9: 39

Changchun 8: 53

Manzhouli 8 degrees 40 minutes

Shenyang 7 degrees 44 minutes

Lvda 6 35'

Beijing 5: 50.

Tianjin 5: 30.

Jinan 5 0 1'

Hohhot 4 minutes and 36 seconds

Xuzhou 4 27'

4: 26 in Shanghai

Taiyuan 4 1 1'

Baotou 4 03'

Nanjing 4 o'clock

Hefei 3 52'

Zhengzhou 3 50'

Hangzhou 3 degrees 50 minutes

Xuchang 3 40'

Jiujiang 3 03'

Wuhan 2 54'

Nanchang 2 48'

Yinchuan 2: 35

Taipei 2 minutes and 32 seconds

Xi 'an 2 29

Changsha 2 14'

Ganzhou 2 0 1'

Hengyang 1 56'

Xiamen 1 50'

Lanzhou 1 44'

Chongqing 1 34'

Zunyi 1 26'

Xining 1 22'

Guilin 1 22'

Guiyang 1 17'

Chengdu 1 16'

Guangzhou 1 09'

Liuzhou 1 08'

Dongsha islands 1 05'

Kunming 1 00'

Nanning 0 50'

Zhanjiang 0 44'

Pingxiang 0 39'

Haikou 0 29'

Lhasa 0 2 1'

Everest 0 19'

Xisha Islands 0 10'

Zengmu shoal 0 24' (East)

Nansha Islands 0 35' (East)

Urumqi 2: 44 (East)