The series consists of a variety of record types, including: topographical maps; index books listing names and data concerning survey stations around B.C.; microfiche with data regarding survey stations in B.C.; library materials on topographical matters and related subjects; and photographs in the form of negative film rolls.
The photo-topographical survey method of mapping was described by R.E. McCaw, B.C.L.S. as follows: "In the mountainous areas of Western Canada, the photo-topographical method for obtaining a topographical map has been used for many years. A triangulation of a fair degree of accuracy is necessary for a base. Rounds of photographs, by specially designed survey camera are taken from the triangulation stations, and many other independent stations which are all connected into a net work of control which may be plotted to scale. It is essential to have all portions of the landscape photographed from two or more different points, which are usually on the summits of mountains or high ridges. The camera is always set in a carefully levelled position. In the office, enlargements from the photographic negatives are made. The directions of these are plotted and points identified from views from adjacent stations overlooking the same area. Using the principles of descriptive geometry and perspective, these points are plotted and the elevations computed. It is always the endeavour to choose the points in such a way they they will outline streams, lakes, ridges, etc. Rivers, creeks, lakes, roads, etc., are then drawn in using the photographs as a guide. The slope is then shown by contours, the accuracy of all depending upon the accurate instrumental work in the field and the number of identified points used in the office."
Descriptive accounts of the survey work in the field is given by surveyors in many of the the departmental annual reports.
The maps in the series GR-3750 were meant by their creator to be used together with photographic prints and negatives which are held by BC Archives in other series; in particular, including: GR-3478 - Photo-topographical images; GR-3427 - Surveys Branch photo-topographical negatives; and GR-3428 - Topographic Division photo-topographical negatives.
Annotations on the maps link to the images, showing survey control stations, the dates a survey was conducted at that station, the surveyor that headed the survey (indicated by either first letters of their full name or by first letter of their last name; and an identifying number of the photograph taken from that station, with an arrow indicating the view (the direction) in which the photograph was taken.
For example, see sheets 93A, Spanish Lake, Swift River and Cariboo Lake; the legend, including annotation to the legend indicates the following, that a “Camera station” is represented by a round circle around a dot, a Triangulation station is represented by a triangle around a dot. A station will have a larger circular annotation with the following as example in the circle:
S = initial of last name of surveyor
1933 = year survey conducted
25 = envelope number (location of stored photographic print)
This indicates that at this station a survey was conducted by Stewart in 1933, and photo prints are located in envelope number 25 of the envelopes of prints in Series GR-3478 - Photo-topographical images. For example: Map 92 I/ SE, Merritt, includes annotations on the map for Iron Mountain region south of the town of Merritt (there are three camera stations at Iron Mountain). The map includes the annotations 24/41, 24/42 and 24/43. These indicate photo prints from the 1924 survey are located in envelopes 41, 42 and 43.
The series is arranged in 12 files; each file is equal to one container. In some cases a container consists of one bound volume. Files one, two and three consist of maps in large, hardcover bound volumes.
File 1 (container 932492-0001) consists of a large, green hardcover binder (61 x 76 x 3 cm) containing 131 maps. Most but not all of the maps are labelled “National Topographic Series.” Items (maps) are arranged in the binder in numerical order according to their NTS number (e.g. 82, 92, 93, 102, 103, 104, etc.). The finding aid for the series (see link below) itemizes each map in this binder.
File 2 (container 932492-0002) consists of 59 topographic maps annotated with survey networks showing triangulation, ca. 1940-1965. The maps, some of which are labelled as pre-emptor’s maps, show triangulation from survey stations, with names of stations. Many are dated as 1942-1945 as the last dates of surveys. The finding aid for the series (see link below) itemizes each map in this binder.
File 3 (container 932492-0003) consists of 41 topographic maps annotated with survey control stations, ca. 1945-1955. The finding aid for the series (see link below) itemizes each map in this binder.
File 4 (container 932492-0004) consists of an index book of survey control stations, ca. 1935-1979. The table format lists data in the following fields: station, district, source, elevation, latitude, longitude, datum, ties to land surveys, and remarks. The primary organization of the index book is in numerical order according to the location (latitude and longitude) of each station. For example, data for stations located at 48-114 is followed by stations at 48-115. These may be broken out into multiple sheets for the same location. The book ranges from a start at 48-113 N.W. and ends at 52-132 N.E.
File 5 (container 932492-0005) consists of an index book of survey control stations, ca. 1940-1979. The table format lists data in the following fields: station, district, source, elevation, latitude, longitude, datum, ties to land surveys, and remarks. The primary organization of the index book is in numerical order according to the latitude and longitude location of each stations. For example, data for stations located at 48-114 is followed by stations at 48-115. These may be broken out into multiple sheets for the same location. The book ranges from a start at 53-118 S.W. to 61-132 S.E.
File 6 (container 932492-0006) consists of 64 forest maps, Interim Forest Cover Series, Canada sheet maps, ca. 1960. Some of the maps are annotated with survey data (location of survey control stations, date of survey, surveyor, photograph taken at station, direction of photo) and some are not.
File 7 (container 932492-0007) consists of 54 forest maps annotated with survey data (Interim Forest Cover Series : Canada sheet maps), ca. 1950-1973. Maps are annotated with survey data (location of survey control stations, date of survey, surveyor, photograph number taken at station, direction of photo).
File 8 (container 932492-0008) consists of 59 forest maps annotated with survey data (Interim Forest Cover Series : Canada sheet maps), ca. 1970. Maps are annotated with survey data (location of survey control stations, date of survey, surveyor, photograph number taken at station, direction of view of the photo, etc.].
File 9 (container 932492-0009) consists of microfiche records of data output from Control Survey Data Base (CSDB). Index and microfiche 1 to 140 represent all B.C. map sheets (82A - 115A). Fiche 1 provides documentation on the data output and sort methods. What follows is a list of fields in the Control Survey Data Base (CSDB): Station Name; Tablet Marking (the number stamped on the marker); CSDB Name (the CSDB computer number); Horizontal Precision Scale H1-H8; Vertical Precision Scale V1-V8; Marked/unmarked Station (Brass bolt, Aluminium disk etc.); Photo Identified or Targeted; Mapsheet #; Date card written; Geographic Co-ords in NAD27; UTM Co-ords / UTM Zone / Central Meridian of the Zone; Roll & Frame # of Photo Identification / Target; Station description; Surveyor / Project Area / Year of Survey; Station site description / marker information; Surveyed rays / Azimuth or Bearing to other stations.
File 10 (container 932492-0010) consists of a sample of a field book (blank) which was retained for evidentiary value; and library materials including books on subjects related to topographical work.
File 11 (container 932492-0011) consists of photographs in the form of negative film rolls, ca. 1950-1953, which include images of river views and other miscellaneous unidentified scenes.
File 12 (container 932492-0012) consists of one map of British Columbia with topographical survey overlay, paper and mylar, British Columbia Ministry of Environment, 1980.
British Columbia. Surveys and Mapping Branch