Getting sundial timed takes some precision

July 05, 1994|By JACQUES KELLY

Is it a meteorite? A piece of sculpture? A huge metal hairball?

The mystery object is Baltimore's most complicated sundial, a bronze and stone instrument that tells time on sunny days.

It sits in a formal flower garden in Druid Hill Park alongside the 1888 Conservatory, one of this greensward's landmark buildings, which faces Gwynns Falls Parkway.

George McDowell, a Union Square resident, sometime sundial maker with a strong interest in ancient scientific principles, heard about this relic donated to the city 102 years ago. He visited the park but was stymied by what he found.

"It was an enigma. It didn't tell the right time. The latitude numbers made no sense. There were errors and mislabels," says Mr. McDowell, who is a lawyer by profession.

The nearly spherical, 14-sided sundial is amazingly complicated. It provides solar time readings for Cape Cod, Baltimore, Rio de Janeiro, San Francisco, Pitcairn Island, Sitka, Honolulu, Jeddo (Tokyo), Calcutta, Cape Town, Jerusalem, Fernando Po (an African island in the Bight of Biafra) and London. There are also dials marked Polar and Equatorial.

But even if the day is bright and there is a strong shadow cast on the dial, the time indicated will most likely not match an accurate watch.

"In 1884 the railroads convinced Congress to enact Standard Time," says Mr. McDowell. When Daylight Saving Time is in effect, a clock in certain parts of a time zone can disagree with sun time by as much as one hour and 45 minutes.

Before this, people used solar time, meaning that noon on Cape Cod arrived earlier than noon in Pittsburgh.

"Dialing was taught in schools as a matter of course before the Civil War. An educated school child would have known how to tell time this way," Mr. McDowell says.

If the Druid Hill sundial posed some tough mathematical questions, so did the origin of the man who gave it to the city.

"This dial was presented to Druid Hill Park by Peter Hamilton, Esq. in 1892," notes the incised bronze plate on one of the dial's facets.

Peter Hamilton was a stone quarryman who was president of the Guilford and Waltersville Granite Co. He had quarries in Woodstock and Granite, and was proud that he supplied 100,000 cubic feet of stone to the Library of Congress.

"I cannot imagine the amount of time it must have taken him to make the hand calculations for all the dials. I checked them with a calculator, and it took me hours for each one," says Mr. McDowell.

"Then, after he's made his calculations, he had to carve the stone with the hours of the day and the names of the places."

Originally, the huge dial was a block of carved granite. It had metal gnomons, triangular-shaped pieces that cast shadows indicating the day's time. About 10 years after it was given to the city, the whole block of granite was encased in bronze plates. Mr. McDowell believes that when this work was done, errors may have found their way into the metal. Three of the gnomons were incorrectly sized.

Worst of all, the sundial was out of line with the north-south axis.

With the city's permission, he worked with local metal artist Larry Lewis to have the dial cleaned of years' worth of dirt. Some of the gnomons had been vandalized. Others needed mathematical correction. Mr. Lewis fabricated replacement pieces.

"I believe in leaving the past pretty much alone. I debated whether to have the bronze pieces changed so they would be correct. I consulted some sundial experts and a Smithsonian curator. They agreed the changes should be made," he says. The city has agreed to underwrite the repair cost.

The lawyer-sundialer developed his deep interest in ancient methods

of calculation while he was a student at St. John's College in Annapolis.

"I went to seven or eight colleges, but they all bored me. I went to Las Vegas and was a dealer for a while. Then I signed up for the Army and learned to be a helicopter pilot and parachutist. When I came back, I went to St. John's on the G.I. Bill. I had my own airplane, a little Taylorcraft, and parked it on campus.

"At St. John's, I became fascinated with Archimedes, Apollonis of Perga and Euclid," he says.

While in college, he and a classmate, Merle Sokolik, translated "The Data of Euclid" from a Greek text. Mr. McDowell recently had his English translation of this scholarly work printed at his own expense.

"It doesn't sell real well," he says. "Maybe one a month."

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