This series consists of published charts produced by the Hydrographic Office of the British Admiralty.

Although the Admiralty Charts were designed to serve as navigational aids, they frequently contain extensive cultural and topographic information. Of particular interest to researchers engaged in First Nations studies is the appearance on early charts of First Nations villages and longhouses. Since the charts were usually based on new surveys, they provide invaluable information on the birth and development of nineteenth century BC coastal communities. Indeed, the charts often serve as the only available cartographic record of early settlements, and may depict such features as Hudson's Bay Company forts; prominent buildings and bridges; farms and field layouts; and railways, roads, and trails.

A guide to the symbols and abbreviations used on the charts is available in Chart X,II (CM/B2423 1911). The chart list identifies for each chart the edition date, as well as the date of the latest large and small corrections. Although the use of the terms edition and large and small corrections changed over time, the practice during much of the period in question appears to have been as follows. A new edition of a chart was generally produced only when the chart was thoroughly revised in content and style. When a chart received changes that were not so extensive as to require the preparation of new edition but were too extensive to be described in the Admiralty Notice to Mariners, the words "large corrections" together with the date of correction were entered near the bottom centre of the chart. When a chart was updated with changes that either appeared in the Notice to Mariners or were considered of no relevance to safe navigation, the words "small corrections" and the date of correction were entered in the bottom left corner of the chart. The number of the Notice in which small corrections were announced was sometimes also entered. Small corrections could be entered on the charts by hand, either at the hydrographic office itself or at the various agencies that sold the charts. Finally, since this series brings together items from diverse sources including other archival record units, it includes a variety of charts annotated by the charts' original users. Items containing significant annotations are identified in the chart list, but researchers are warned that in many cases it will be impossible to identify the persons responsible for the annotations.

The item consists of a photocopied version of the "Hydrographic instructions for Captain George Richards, about to proceed to Vancouver's Island," March, 1857. The instructions from the British Admiralty were for Captain Richards, in command of the survey vessel Plumper, to make a detailed survey of the waters between Vancouver Island and the American mainland, to help determine the location of the international boundary through the San Juan Islands.

The series consists primarily of small, hard-cover notebooks used for recording data in the field during hydrographic survey projects. It also consists of envelopes containing various textual and cartographic records. The purpose of the records was to document information recorded by Water Management Branch field surveyors when they completed hydrographic surveys. Information was used as reference material in preparation of topographical maps. Also recorded was information relating to projects completed by the Water Branch (such as irrigation projects). Also recorded was information of the time regarding claims and claimants to water rights. The records may have a high degree of long-range research value.

Many of the field books contain data for so many different geographic locations, it was impossible to list or reflect each location in the file titles.

Relevant information is to be found in many Dept. of Lands, Water Rights Branch annual reports, where the background and execution of the hydrographic surveys around the province are discussed. See for example the Sessional Papers of British Columbia, Session 1913, pgs. D 107 to D 222.