Sundials: find a place in your garden for mankind's oldest timekeeper - the sun

Flower & Garden Magazine, Oct-Nov, 1995 by Steve Trusty

Communicating by means of shadows, sundials silently mark the passage of time. Although we no longer rely on them as timepieces, sundials are an attractive and nostalgic addition to modern gardens.

Sundials used thousands of years ago in Egypt are still in existence. Those early sundials divided the period from sunrise to sunset into the same number of equal parts throughout the year. As the length of daylight varied from season to season, so did the length of the "hours." An hour in summer was longer than an hour in winter.

The Babylonians developed a hemispherical sundial around 300 B.C. Ancient Greeks and Romans used their ingenuity to develop sundials with added complexity, including a portable style, the "pocket watch" of that period. Many sporting goods stores offer modern versions of a portable sundial combined with a compass.

The greatest improvement in sundial accuracy came in the first century A.D. It was discovered that by slanting the gnomon (the shadow arm) so it was pointing to the celestial pole, the direction of its shadow would indicate solar time correctly. It was still many centuries before hours of equal length were universally accepted.

As mechanical clocks and watches were invented, their use began to supersede sundials, but not completely. Sundials were needed to assure the accuracy of the newfangled gadgets. Sundials were placed next to clocks on some old European towers to verify the mechanical accuracy.

After clocks became more reliable, sundials remained on the scene as garden ornaments. In today's gardens, their charm spans all seasons.

Sundials vary from plain to fancy, and can be cast in metal or carved' from stone. Place a sundial on a pedestal in a flower bed or where paths join, and you will have a focal point that invites close scrutiny in a way no other garden onament can.

In a small, informal setting, a sundial may be surrounded by colorful wildflowers or mixed annuals and perennials. A more structured effect can be achieved in a haven of trimmed green shrubbery or a formal herb bed. Another idea is to simply place the sundial in an expanse of green grass, where it will draw the eye from a distance.

When placing your sundial, choose a spot in full sun. Make sure the dial is level. Rotate the sundial so the gnomon is pointed toward celestial north (south in the Southern Hemisphere), not the magnetic north of a compass.

The easiest way to find celestial north is to put your sundial in place at noon. Turn the dial until the shadow of the gnomon falls directly on the noon mark on the dial. For optimum accuracy, set your dial on one of the four days of the year that that sun time and clock time agree (see "The Equation of Time"). Although you may use your sundial primarily for ornamental purposes, why not take advantage of its time-telling benefit as well?