Yangshi Lei Archives

The royal construction engineering system during the Qing dynasty is supervised by the Ministry of Works and conducted by a team that formed from craftsmen recruited nationwide. The Pattern Design Office and the Building Estimate Office were set under the Ministry of Works. The Pattern Design Office was in charge of construction design, while the Building Estimate Office estimated the cost of labour and materials.[8]

In the design process, drawings, models and building method texts were based on the Official Manual of Constructional Engineering, a technical book that specified building methods published by the court. The first construction method guide book can trace back to the Treatise on Architectural Methods (Yingzao Fashi) published in 1103 during the Song dynasty. The drawings demonstrate the layout, elevation of buildings and decorating details. The models are the visualization of the buildings with size and methods marked on them. The text documents specified the construction method and record the daily process.[9]

The contents in the graphical samples cover the process of each stage of construction, including site survey, planning, construction method and working notes. In terms of representation, they contain drawings of floor plans, section and elevation. They were drawn and written in ink-brush, charcoal on traditional Chinese paper.[3] Among all Yangshi Lei drawings, the largest sketch is approximately six meters in length, whereas the smallest piece is about six centimetres.[7]

The drawings use particular legends and labels to represent the size, shape, structure, location, function and other relative information needed in construction. On the drawings for new projects, "tags" written on red or yellow paper are attached to indicate the date of the building's parts, such as "bay-dimensions", "building depth", "height of column", "diameter of the column" and so on. Information about colours and shapes are also found on the tags.[2]

During the site survey process, in order to record the three-dimensional topographic features, they used the grid system to projection three-dimensional data on two-dimension paper. A grid system is first drawn from the site centre towards four directions. The scale of the grid depends on the dimension of the layout. Then, at the intersection points of the grid, heights of the land were noted beside.[10] Therefore, the height of the terrain as well as the plane area can be calculated. The grid system was used for site survey and construction planning stage. According to the study of Wang Qiheng, the grid system used for topography survey is "fully compatible with the concept of the Digital Elevation Model (DEM) nowadays."[8]

Techniques of "layered images, direct parallelism, and perspective shadowing" are also used to represent the three-dimension structure of the buildings. These drawings for technical use are all held by the Lei family themselves outside the court.[3]

The Yangshi Lei Archives collection includes building models namely the "ironed models" (Chinese: 烫样; pinyin: tàng yàng). These ironed models were sent to get viewed and the official approval from the emperor, before conducting further construction method design and cost accounting.[9]

The components of Yangshi Lei ironed models were made from cardboard, soft white spruce, red pine and sorghum stalk, and then ironed to fortify the model structure.[11] It is named "ironed" due to this ironing process. They are made into a scale ranging from 1:200, 1:100, 1:50 to 1:20. The surface of the models was coloured according to the design manuscript. The information on building materials and dimension are labelled on the models.[10] The models can generally be divided into three types: the global complex, the individual buildings, and the detailed pieces.

The individual buildings visualize the outer and inner structures, and the detailed pieces focus on partial particular furnishings decorations. In an individual building model, the parts of those models can be disassembled. The roof can be removed so that a closer look of inner structures and interior decorations can be seen.[1][10] The individual building model "Dian Men" is an instance of single building model with hip-and-gable roof. Its roof part can be removed, and the timbers and column structures inside can be seen in detail. The paintings and patterns on eaves and interior decoration are also clear. Notations of dimensions and name of component parts are attached.[5]

In addition to a single building, the global complexes visualize the layout of space, connection of buildings and the surrounding environment. Usually, the layout of the Ancient Chinese complex forms to a courtyard consisting of buildings and surroundings. There are mountains, height and flow direction of streams and rivers shown in most of the complex models.[5]

The earliest research on the Yangshi Lei Archives was led by Zhu Qiqian, who was the founder of the Society for Research in Chinese Architecture.[3][6][12] He helped with the first purchase and collection of the National Library of China. On 21 March 1931, Zhu held an exhibition called "Historical Documents and Artifacts of the Old Summer Palace (Yuanming Yuan)". A large part of the exhibits was from the Yangshi Lei Archives.[10] Zhu saw this archive as one of the keystones in research of the ancient Chinese architecture design, as well as the Song Treatise on Architectural Methods (Yingzao Fashi) and Qing Official Manual of Constructional Engineering, due to its large scale and coverage on each step of building design. Research in the stage first catalogued the drawings and models.[13]

This stage focuses on the utilization of the Yangshi Lei Archives on renovations of the Summer Palace, the Old Summer Palace, and so on. More categorizations are completed.[7]

Two main institutions concerned with Yangshi Lei Archives research are the School of Architecture at Tianjin University and Tsinghua University. They centre on the Yangshi Lei Archives with relative architectural theory, and digital reconstructions of the Old Summer Palace respectively.[7]