Sundial in Bac Lieu province

Center for Continuing Education of Bac Lieu city, Bac Lieu province, has a special historic monument: a weird solar clock approximates 100 years old

“Thai Duong” clock (Sun clock) was set up in front of Bac Lieu Governor’s house in French colonialism. “Father” of this clock is Mr. Luu Van Lang (1880 – 1969), a famous scientist of the South in the beginning of 20th century.

The clock has fairly rudimentary structure, the surface faces East. It is made by brick and cement, about 0.7 meter high and 1 meter wide. The dial is an inclined cross section, and a vertical rectangular protrudes in the middle.

Twelve Roman numbers were hand-carved on the dial, from 1 to 12 to indicate hours, The middle of numbers is divided into 12 areas to indicate minutes.

Operational principle of this clock is simple. Sunlight radiates the rectangular which will create a shadow mark on the dial. Time is determined based on this trail.

Shadow of sunlight on this clock rotates clockwise, in the same direction with common clock, therefore, in this image, hour number is 10.

The “minute hand” is located between line 8 and 9 in 12 minute lines of 10th hour. Each minute line equal 5 minutes, so minute in this picture is 8,5 * 5 = 42,5 minutes. In fact, when the picture is taken, the camera’s clock is 10.39am. Thus, the error of the solar clock in this case is approximately 3 minutes.

As a rudimentary clock, this accuracy is very impressive.

The biggest drawback of the solar dial is its “operation” by the sun, so the clock will “die” in dark or cloudy day.

The sun clocks emerged from the period of the ancient civilization. It is interesting is that the design of solar clock in Bac Lieu is unlike any other sundial which is ever known in the world.

Source: REDS.VN

Translated by Me.