The first Seismoscope invention was unveiled in 132 CE. Under the name “Houfeng Didong Yi”* Imperial Historian Zhang Heng presented his invention to the Han Court. Descriptions of the first seismoscope were shaped like a barrel, equipped with eight dragons clinging onto the vessel facing downward at set intervals, each carrying a ball within its mouth. Beneath each dragon a frog is seated, mouth open in anticipation, in the event that the device detects an earthquake. Unlike the wooden replica that is housed in the Cultural Centre Museum, the original Seismograph was said to have been 6 feet in diameter and forged in bronze.

As intricate as the design was, historians are unsure of how the Seismoscope device functioned. One theory suggests that a thin rod is carefully balanced within the center of the device. When detecting an earthquake, the rod falls in the direction of the tremors causing the dragon to drop the ball into the mouth of an assuming frog. The sound of the ball dropping into the frog's mouth would alert those nearby to the seismograph's activity, while the position of the dropped ball would indicate the earthquake's direction of origin. The device was unable to measure the magnitude of the earthquakes.

*Meaning, "An Instrument for measuring the winds and movement of the Earth".

在公元132年，御史學家張衡發明了第一個地震儀，並以「侯風地動儀」*之名，將其發明呈獻給漢朝。第一個地震儀的描述形容其形狀就像一個桶，並配備了八條龍。每條龍都以固定的間隔向下貼在容器上，嘴裏都夾著一個球。在龍的下方則坐著一隻青蛙，嘴巴張開以檢測地震。與收藏在文化中心博物館的木造複製品不同，據說原始的地震儀直徑長達6英尺，並由青銅鑄造而成。

由於設計很複雜，歷史學家亦不能確認地震儀究竟是如何運作的。一種理論指出在儀器的中心有一根仔細平衡的細棒。當檢測到地震時，棒子會朝著震動的方向落下，導致龍把球扔進一隻假想的青蛙的嘴裏。球落入青蛙嘴裡的聲音會提醒附近的人注意地震儀的活動，而落球的位置則會指示地震的起源方向。然而，儀器卻無法測量地震的級數。

*意思是指「測量地球的風和動線的儀器」。