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Double nodus sundial

Rijswijk

Here are two almost-south vertical dials. One declines ten degrees to the east, the other ten degrees to the west.

One sundial is used during the lengthening days, the other during the shortening days.
lengthening days: 23 December to 21 June
shortening days: 21 June to 23 December

The sundials show date lines for the first of each month, and for the four seasons.
They indicate civil time. The hour lines incorporate both longitude adjustment and the equation of time.

Having the equation of time loops split between two sundials simplifies reading considerably.

Both sundials are nodus dials. The terminus of a pyramidal body is the shadow-casting object.

Here are the patterns of both sundials, slightly larger.