i.e. 380 × 5 = 1900 yards.
What is the aurora borealis or northern lights?
Luminous appearances seen in the sky at night-time. Sometimes streaks of blue, purple, green, red, etc., and sometimes flashes of light, are seen.
What is the cause of the aurora borealis or northern lights?
Electricity in the higher regions of the atmosphere is undoubtedly an active agent in producing this phenomenon.
Is the aurora ever seen in other parts of the heavens than towards the north?
In the northern hemisphere it always appears in the north, but in the southern hemisphere it appears in the south: it seems to originate at or near the poles of the earth, and is consequently seen in its greatest perfection within the arctic and antarctic circles.
What is known concerning the extent of the aurora?
It is not local, but it is seen simultaneously at places widely remote from each other, as in Europe and America.
What calculations have been made respecting the height of the aurora?