102 



The Midnight Sun. 



At the equator the light and shaded parts are of equal extent, 

 and the days and nights are equal, as is always the case there. 

 At the Tropic of Capricorn, the light, and shaded portions are 

 unequal, but inversely to the Tropic of Cancer, and there are 

 short days and long nights. At S, and adjacent to it, so far 

 as the Antarctic circle, the earth's rotation produces no emer- 

 gence out of the shaded part, and the night is therefore 

 continuous. 



FIG: s. 



El'i 



Fig. 5 represents the effect of the sun being over the 

 equator, as he is in March and September, instead of over the 

 Tropic of Cancer ; the days and nights are then equal all over 

 the world — the axial rotation exposing every part of the 

 earth's surface to the same amount of light and darkness. 



no. e 



Fig. C shows the sun over the Tropic of Capricorn, as he is 

 on the 21st of December, having the greatest south declination 

 be attains, and explains the southern summer, and the short days 

 and long nights of our winter. Here no portion of the surface 

 included in the Antarctic circle can escape from the sun's light, 

 and the phenomenon < >f the sun continually above the horizon 

 Will be witnessed by any person reaching a high southern latitude, 

 as well as in the north, which haa hitherto claimed our attention. 



