Chinatown, San Francisco, California 1885 (Raster Image)

This layer is a georeferenced raster image of the historic paper map entitled: Official map of Chinatown in San Francisco, prepared under the supervision of the special committee of the board of supervisors, July 1885, W.B. Farwell, John E. Kunkler, E.B. Pond. It was engraved & printed by Bosqui Eng. & Print Co. in 1885. Scale [1:480]. This image consists of images of a two sheet source map that have been stitched together using image editing software to create one image. The image inside the map neatline is georeferenced to the surface of the earth and fit to the California Zone III State Plane Coordinate System NAD83 (in Feet) (Fipszone 0403). All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This cadastral map shows features such as roads, buildings with street addresses and types of businesses, and more. Buildings colored to show: general Chinese occupancy, Chinese gambling houses, Chinese prostitution, Chinese opium resorts, Chinese Joss houses, and White prostitution. This layer is part of a selection of digitally scanned and georeferenced historic maps from The Harvard Map Collection as part of the Imaging the Urban Environment project. Maps selected for this project represent major urban areas and cities of the world, at various time periods. These maps typically portray both natural and manmade features at a large scale. The selection represents a range of regions, originators, ground condition dates, scales, and purposes.

Historic paper maps can provide an excellent view of the changes that have occurred in the cultural and physical landscape. The wide range of information provided on these maps make them useful in the study of historic geography, and urban and rural land use change. As this map has been georeferenced, it can be used in a GIS as a source or background layer in conjunction with other GIS data.

source map publication date.

map.

None.

The georeferenced raster is a faithfully reproduced digital image of the original source map. Some differences may be detected between the source graphic used and the raster image due to the RGB values assigned that particular color. The intent is to recreate those colors as near as possible. Data completeness for raster digital image files reflect content of the source graphic. Features may have been eliminated or generalized on the source graphic due to scale and legibility constraints The horizontal positional accuracy of a raster image is approximately the same as the accuracy of the published source map. The lack of a greater accuracy is largely the result of the inaccuracies with the original measurements and possible distortions in the original paper map document. There may also be errors introduced during the digitizing and georeferencing process. In most cases, errors in the raster image are small compared with sources of error in the original map graphic. The RMS error for this map is 3.48788 feet. This value describes how consistent the transformation is between the different control points (links). The RMS error is only an assessment of the accuracy of the transformation.

ESRI ArcCatalog 9.2.

Not applicable.