A primary astronomy .. . MEASURING THE SUN S DECLINATION IN NORTHERN 3. This cut shows how the student may measure the Suns declination wherever hemay be located north of the equator. The shadows are such as are cast by objectsduring the year, about 45° north of the equator. On the 23d of December, when theSun has his greatest declination, the shadow of the flag-staff extends north at 12oclock to the point C, where two boys are seen, having just driven down a this time to June 21st the shadow gradually shortens, till on that day it reachesthe point B, where another stake
A primary astronomy .. . MEASURING THE SUN S DECLINATION IN NORTHERN 3. This cut shows how the student may measure the Suns declination wherever hemay be located north of the equator. The shadows are such as are cast by objectsduring the year, about 45° north of the equator. On the 23d of December, when theSun has his greatest declination, the shadow of the flag-staff extends north at 12oclock to the point C, where two boys are seen, having just driven down a this time to June 21st the shadow gradually shortens, till on that day it reachesthe point B, where another stake is driven. It then begins to elongate, and in sixmonths is extended to C again. The point A is just half way from B to C in angularmeasurement, though the distances on the plain in the picture are very different. PEIMARY ASTRONOMY. 81 When the Sun is on the equator, March 21st and September 23d, the shadow willreach only to A; and the angle A B and the top of the staff shows the northern, andA C and the top of the staff the southern declination. It will be found to be 23°
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Keywords: ., bookcentury1800, bookdecade1850, booksubjectastronomy, bookyear18
