above: SUNDIAL --- below: ADJUSTMENTS
SUNDIAL
Standing at vertical height of approximately 5 feet, the 7 foot stylus projects a shadow onto a 12 foot diameter circle of bricks embedded in the ground. The angle of the stylus is determined by the latitude of Lawrence, Kansas, which is approximately 39 degrees. True north was approximated by adjusting seven degrees clockwise from magnetic north.
Special stones mark the hours of the day. The big log behind the sundial has an adjustment chart carved into it.
The sun is actually directly overhead Lawrence at about 12:20 p.m.
SEASONAL ADJUSTMENTS FOR THE EARTH'S WOBBLE
First read the time as indicated by the sundial's stylus shadow.
Go to the graph, find the time of year, and then add or subtact minutes as indicated to arrive at the corrected time.
If the sun is casting a shadow, it is relatively easy tell the time to within 5 minutes of the actual time all year long.
The most extreme adjustments come in middle February, when one must add about fifteen minutes,
and in early November, when one must subtract nearly 18 minutes from the shadow time.
