Tsinghua sundial collection location: Tsinghua University history, cultural relics protection, history The classical timer sundial is located at the south end of the front lawn of Tsinghua University Auditorium, which is a commemoration of the graduation of 1920 (Gengshen) students. The upper part is in the shape of a sundial, and the lower base is engraved with the inscription 1920: "Actions speak louder than words" in Chinese and Latin, as well as the date of construction. The sundial is a simple timer in ancient China. Its function is to indicate the time by using the position of the shadow produced by sunlight on the inclined pointer. Generally, the stainless steel pointer is placed in the center of a carved disk, and then the disk is reclined on a platform, with the south high and the north low, so that the upper pointer points to the North Pole and the lower pointer points to the North Pole. There are twelve points engraved on the top and bottom of the disk, "Zi Chou …". When the sun is due south, the shadow of the needle is just in the direction of due north, which is noon. After the vernal equinox every year, look at the shadow on the disk; Look at the shadow below after the autumnal equinox. 1920 grade is one of the excellent graduation grades in Tsinghua University. Famous professors of economics (who served as dean of the Law School of Tsinghua University for a long time), Zeng Zhaolun, Zeng Zhaolun, Zeng Zhaotuo and Zhao, and Hsiao Kung chuan, a botanist and political scientist, are all in this grade. A friend of Chen Sancai's level is an excellent patriot. During his stay in War of Resistance against Japanese Aggression (1940), he was trapped behind enemy lines for failing to murder the rebel general Wang Jingwei. After being tortured, he was brutally killed by Wang's followers in Yuhuatai, Nanjing on February 2 of that year. Cultural Relics Protection On August 7, 2065438, the sundial in front of the lawn of Tsinghua University Auditorium was found with traces of carving. The pictures provided by students in Tsinghua show that the carving marks are located in the upper part of the surface, and there are more than a dozen strokes, which are pale white and very abrupt. As soon as this matter came out, it was widely concerned by the society. The school said that after the discovery, the school immediately started the investigation and repair procedure. On 20 18, some netizens posted that the sundial, a landmark scenic spot in Tsinghua University, was misspelled. According to the post, the text "1920 grade" on the east side of the sundial pedestal was written as "CEASS 1920" and painted in gold. On-site photos show that there are two obvious nicks on the letter "L", which are very similar to the letter "E" at first glance. On April 17, Beijing Youth Daily reporter learned from Tsinghua University that at present, the staff of the logistics department have redrawn the "E" on the sundial base as "L" and repaired two nicks.