Australia’s National R502 Map Series : A Tribute to the Forgotten Mappers of the Ghastly Blank
by Paul Wise, originally presented titled ‘Australia’s First 1: 250 000 Scale, Uniform Topographic Map Coverage : The R502 Story’, updated, re-edited and re-titled for the web 2023
Introduction
The 1: 250 000 scale R502 series of maps was the first uniform medium scale topographic map coverage of Australia. Each standard map sheet covered an area bounded by 1.5 degrees of longitude and 1 degree of latitude (about 150 kilometres from east to west and 110 kilometres from north to south). At 1: 250 000 scale, 1mm on the map represents 250 metres on the ground. The R502 series comprised a total of 540 printed maps (Division of National Mapping 1968). Production of the R502 map series commenced around 1956. All sheet compilations were finalised by 1966 and printing of all the maps of the series was completed by the end of 1968. The Division of National Mapping and Royal Australian Survey Corps each compiled around 40 per cent of the map sheets. State mapping authorities in Western Australia (17%), Queensland, Tasmania, and South Australia compiled the remainder. The Royal Australian Survey Corps and National Mapping were responsible for printing all of the map sheets. Private sector organisations supplied some horizontal control (such as from petroleum exploration surveys) as well as various other services under contract. Thus, completion of the R502 map series involved an outstanding national peace-time co-operative effort. Australia’s mapping infrastructure continued to strengthen after completion of the R502 map series. By 1991, densification of horizontal and vertical control networks was such that the R502 series was replaced by the 1: 250 000 scale National Topographic Map Series (NTMS). The NTMS series was compiled at 1: 100 000 scale and the new 1: 250 000 scale map sheets were derived from the 1: 100 000 scale compilations (O’Donnell 2006).
|
|
|
Figure 1 – (Left) Copy of 1846 map of Australia by John Arrowsmith; (Right) Map showing regions of Australia that were still unmapped circa 1945.
As late as 1963, the still largely unknown and unmapped Australian interior was the ghastly blank (Morehead 1963), as maps of the time were still showing vast regions of inland Australia as empty spaces. Please refer to Figure 1 above. The term had first been used in an editorial in the Melbourne Argus (The Argus 1858) newspaper when promoting the then proposed Burke & Wills Expedition of 1860. In the then intervening 105 years, despite Burke & Wills and other explorers on foot and even Halligan in the 1920s and MacKay in the 1930s, using aircraft, much of the ghastly blank still remained. Even the intense mapping efforts of the Emergency Mapping Scheme of World War Two, when a Japanese invasion was feared, left a significant portion of Australia a ghastly blank.
Before he retired, the longest serving Director of National Mapping, Bruce Philip Lambert (1912-1990), stated in his 1976 paper Topographic mapping in Australia : Development 1945-1975, most of the early topographic mapping in Australia was built up from the reports and surveys of explorers supplemented as time went on by the somewhat meagre data collected in the course of cadastral and engineering surveys. There is no doubt that the early surveyors were aware of the desirability of planning development on the basis of good topographic maps but the exigencies of the situation, the non availability of funds and lack of skilled manpower dictated the course of events and top priority had to be given to land surveys. Lambert, however, was not raising a new issue as history showed that when mapping priorities were being determined mapping the topography always had a low priority. Even at around the time of the first settlement of Australia, Rachel Hewitt in her 2010 book Map of a Nation : A biography of the Ordnance Survey, wrote that in England William Mudge (1762–1820), a commissioner of the Board of Longitude established to assess methods for finding longitude at sea, as well as computing UK triangulation, was arguing for relinquish[ing] the prosecution of the very minute part of the Survey to attend to what is of real use to the Public at large, thus giving higher priority to inclusion of the landscape. The 2021 paper Baselines for Geodetic Triangulation Surveys in Australia, describes some of the earliest surveys for to[ographic mapping in Australia.
The economic enormity of the mapping task for Australia at the time is indicated in Table 1, which shows the area of Australia and its 1954 population compared with those of the United States and Canada. Simplistically, every square kilometre of mapping in Australia was to support just over one person, whereas in Canada, it was nearly two people and in the United States, it was over 16 people.
|
Country |
Australia |
Canada |
U.S.A. |
|
1954 Population |
9 million |
15 million |
163 million |
|
Area (square kilometres) |
7.7 million |
9.1 million |
9.8 million |
|
People per square kilometre |
1.2 |
1.7 |
16.6 |
Table 1 : Comparison of Populations and Areas in Selected Countries.
Note: Data for this table came from various Google searches. The 1954 Australian population figure is the actual census figure. Canada and USA are of comparable areal size to Australia.
With such a low population base and coming just after World War 2, it is perhaps understandable that the R502 mapping program was beset with problems of funding as well as those of bureaucracy and changing of priorities. As Lines (1992) pointed out, in the period just after the war, the lack of trained staff continually impacted progress. Nevertheless, the program was successfully completed in around 12 years.
In tracing the evolution of the R502 series of topographic mapping, this paper outlines the demands for the topographic mapping of Australia. It also outlines the post-Federation Commonwealth government administrative arrangements for topographic mapping that emerged in response. The subsequent establishment of the R502 series topographic map program with decimal scale, the slow start to this program, its component parts and its achievement are then discussed.
The plan emerges
Commonwealth Gazette No. 1, of 1 January 1901 established the Department of Home Affairs to carry out a servicing role. While surveying and mapping functions were seen as appropriate for a servicing department, none were ceded by the States to the Commonwealth at Federation. However, with the passing of the Commonwealth Lands Acquisition Act of 1906, a number of surveying and mapping functions transferred from the States to the Commonwealth. This legislation allowed the Commonwealth’s small, civilian mapping requirement to be met by the Lands and Survey staff of the Department for Home and Territories (Anon 1964).
At this same time surveying professionals were criticising the fact that the colonies had failed to deliver a consistent topographic survey. While the early surveyors were undoubtedly aware of the desirability of planning land development on the basis of good topographic maps, the non-availability of funds and the lack of skilled manpower resulted in cadastral surveys getting higher priority. Henry Edward Coane in a paper for the Victorian Institution of Surveyors in 1901, stated :
In none of the Australian Colonies has any serious attempt been made to conduct a general systematic topographical survey, although the necessity has long been urged by the Technical Associations (Coane 1901).
The genesis of systematic topographic mapping in Australia is considered to be 1907, when the Defence Forces commenced producing strategic maps and plans by adding contours and topographic detail to existing cadastral material (Lambert 1976). This methodology was found to be inefficient, as the cadastral mapping was generally unrelated to a homogeneous base. The Survey Section of the Royal Australian Engineers (RAE) was established in 1910, now using the existing State triangulation systems as the control framework for their topographic maps. By 1914 their own geodetic sub-section was formed to perform triangulation ahead of the topographers. These two events saw the topographic mapping of Australia (at 1:63,360 or 1 mile to 1 inch scale also called One inch) deemed worthy of resourcing (Coulthard-Clark 2000). The Survey Section of the RAE became the Australian Survey Corps in 1915 and subsequently the Royal Australian Survey Corps (RA Survey) in 1948. For simplicity, RA Survey is used throughout this paper when referring to the Survey Corps of the Australian Army.
A resolution from the Conference of Surveyors-General in Melbourne during 20-25 May 1912 contained detailed proposals for a National Geodetic Survey of Australia. That conference recognised that such a geodetic survey was absolutely necessary for the production of accurate maps (Conference of Surveyors-General 1912). During World War 1 (1914-1918), Australia focussed nationally on the war effort and many survey and mapping personnel served overseas. On their return from this service, many of these personnel were employed by the States’ survey organisations.
In 1921, topographic mapping became a Commonwealth responsibility within the Lands and Survey Branch of the Department of Home and Territories. Notwithstanding this development and the pockets of RA Survey One inch mapping work, nationally there had been no progress on survey or mapping. The need for a national geodetic and topographic survey of Australia was again highlighted during the first Interstate Conference of the Australian Surveyors’ Institutes, held in Melbourne in November 1927. At that conference, the Director of Commonwealth Lands and Surveys delivered a paper: The Need for a Geodetic Survey of Australia. In this paper, the Director described a topographic survey with contours (derived from aerial photography) as being vital (Percival 1928). In addition, the President of the Surveyors' Institutes contributed a paper: On the Need for a Topographical Survey of Australia (Montgomery 1928). The Institutes’ President was forthright in observing that Australia had lagged behind other Commonwealth countries in mapping and asked how long was Australia prepared to continue to do so. Apart from the economic benefits, the President stated that every pound spent on good maps was an insurance against loss and disaster in the military field. These were prophetic words indeed in the light of Australia’s mapping situation at the outbreak of World War 2 in 1939.
The lack of adequate topographic map coverage of Australia was further highlighted by the Victorian representative of the Development and Migration Commission. He requested that delegates to the 1927 Conference assist in the preparation of a statement on the need for topographical maps of Australia. Submissions were to be forwarded to the conference President for consolidation and subsequent presentation to government. To follow through on this request, the Australian Survey Committee - ASC (not to be confused with the later Commonwealth Survey Committee) was formed. This committee had representatives from surveyors, engineers, mining and metallurgy, academia and the Victorian Government Astronomer. The Development and Migration Commission provided the secretary. Input was also received, from the Defence department and the Director of Commonwealth Lands and Surveys (Australian Survey Committee 1929).
In October 1928, the chair of the Development and Migration Commission requested that the chair of the ASC put forward a national scheme of topographical mapping. This scheme was contained in the Report on the Need for a Geodetic and Topographical Survey of Australia (Australian Survey Committee 1929). The ASC concluded that it was essential for a first order geodetic survey to be carried out, so that adequate topographical maps of Australia could be produced and all survey work could be co-ordinated. ASC also proposed the formation of a national committee, not unlike the later National Mapping Council, be formed. This first ASC report was presented to the Commonwealth government on 18 February 1930.
The government claimed stringent financial limitations prevented take up of the report’s recommendations; but left some hope by indicating that the recommendations might be reconsidered at a better time. In 1932, the Department of Interior was created (Commonwealth Gazette No. 33 of 14 April 1932) and the Commonwealth’s surveying, mapping and property functions were transferred to that department. However, there was still no action on the ASC’s recommendations. The ASC met again on 27 September 1933 and considered whether the Commonwealth government should again be approached to start the geodetic and topographical survey of Australia. However, as there had been general economic improvement and additional information collected in the intervening years, ASC decided to submit a second report. This second report also advanced that the scale of 1 mile to 1 inch was the most useful for such topographical mapping. These recommendations supported an agreement reached in November 1929 between the Surveyors-General of the States and a representative of the Defence Department to facilitate future topographical mapping. The ASC’s second report was presented to the Minister for Development, on 23 November 1934 (Australian Survey Committee 1935). Unfortunately, as with the ASC’s first report, this second report received little Commonwealth government support.
With the commencement of a number of major independent survey and mapping activities in early 1935, the chair of the ASC, the Department of Defence and the Institution of Engineers, Australia saw the need for a co-ordinating body and voiced such opinion to the Commonwealth government. The government’s response was to establish the Commonwealth Survey Committee (CSC) in late 1935 with a view to ensuring the future co-ordination of surveys throughout Australia. The CSC was chaired by the Commonwealth Surveyor-General, with representatives of the three Defence services (Navy, Army and Air Force). Co-ordination with the States was achieved through the Commonwealth Surveyor-General. The CSC reported in 1936 but its recommendations were deferred and as World War 2 intervened, they did not meet again until August 1944. In 1937 Frank Debenham the learned Australian geologist and then chair of Geography at Cambridge wrote to the Department of Interior saying that he was :
Dismayed at the paucity of topographic information in Australia and aware of the backwardness of my country in the matter of fundamental surveys … that triangulation should be in the hands of the Federal Government… no topographic map of any real value can be made without such a framework.
During 1930-37, Donald George Mackay led four private aerial survey expeditions to map the largely unknown Australian interior. For the first expedition in 1930, a base camp was established near llbpilla Soak about 350 km north-west of Alice Springs. From there the work extended radially out to a distance of about 250km. This expedition found a very large, dry lake astride the Western Australia /Northern Territory border. This lake is now known as Lake Mackay. A second expedition took place in 1933 and operated from Docker River in the Northern Territory and Roy Hill and Fitzroy Crossing in Western Australia. The three base sites formed a triangle with sides about 1 000 kilometres in length (the range of Mackay’s aircraft). From these bases, large areas of the Great Sandy and Gibson Deserts were surveyed. Mackay’s 1935 expedition surveyed a strip of country about 1 400 kilometres long and about 500 kilometres wide, immediately to the north of the Transcontinental Railway. It used bases at Cook, Forrest, Laverton, Oodnadatta and Rawlinna. Mackay’s fourth and final expedition in 1937 was based at Tanami (about 470 kilometres due west of Tennant Creek) and Roy Hill again. The 1937 expedition filled in some gaps from previous flights (Canon 1987). Although the final maps could only be regarded as reconnaissance, nonetheless they portrayed significant topographic features. The areas of Mackay’s surveys are shown in Figure 2.
At the outbreak of World War 2, less than 2 per cent of Australia had been mapped at One inch. This coverage comprised some 80 map sheets (approximately 40 000 square miles) in New South Wales, Victoria and Queensland. This coverage is shown in Figure 3a. A result of RA Survey’s own efforts, this mapping was produced post World War 1 at an average rate of about 4 map sheets per year (Lambert 1969). The Commonwealth Surveyor-General (who later also became the first Director of National Mapping), recalled: ‘the inadequacy of our maps became more fully apparent when the Japanese were on our threshold in 1942. It is probable that they were better informed on the topography of parts of New Guinea then we ourselves were’ (Johnston 1962). This predicament led to the instigation of the Emergency Mapping Scheme in November 1940. The Scheme’s first step was to accelerate the One inch mapping program but it soon became evident that the required emergency timeframe for completion was completely unachievable. While mapping at One inch continued, new series at 1: 506 880 (8 miles to 1 inch) scale and 1: 253 440 (4 miles to 1 inch) scale were commenced. To fulfil the Scheme’s requirements photo-mosaics were also prepared. During World War 2 topographic map coverage advanced significantly. Some 60 map sheets at 1: 506 880 scale, 230 sheets at 1: 253 440 scale, and 342 sheets at 1: 63 360 scale map sheets were produced (172 sheets at the 1: 63 360 scale being Standard Editions). This coverage is shown in Figure 3b. However, owing to the necessarily tight production timeframe, the quality of this mapping varied (Lambert 1969).
Figure 2 – Areas covered by Mackay’s expeditions between 1930 and 1937.
The August 1944 meeting of the Commonwealth Survey Committee (CSC) passed thirteen resolutions. Resolutions 2 and 3 recommended the adoption of the 4 miles and 1 mile to 1 inch map series (as were being produced by RA Survey at that time) as the basic type of map for a national survey. Further, the CSC held the opinion that as a national undertaking, a national survey should be financed by the Commonwealth. CSC’s Resolution 12 recommended that, at their next meeting the State Surveyors-General confer with the Commonwealth Surveyor-General and the Commonwealth Survey Committee. This resolution gave rise to the Commonwealth Survey Committee and State Surveyors-General Conference of 15-19 January 1945 (Commonwealth Survey Committee undated). The recommendations of that conference received Commonwealth government approval on 7 March 1945 and provided for the formation of the National Mapping Council (NMC).
The new National Mapping Council was to be chaired by the Commonwealth Surveyor-General who was also to be the Director of National Mapping. This new Director was responsible for the co-ordination of the activities of Commonwealth and State authorities in planning and carrying out the National Mapping of Australia with full regard to the recommendations of the National Mapping Council.
Figure 3a – Topographic Mapping (One inch scale) coverage in 1939 (Tyson 1965), of the total of 165 maps shown,18 were known to be Manoeuvre maps and 60 Tactical maps.
Figure 3b – Topographic Mapping coverage in 1945 at the conclusion of the Emergency Mapping Scheme (Tyson 1965).
Figure 3c – Topographic Mapping coverage in 1950 (National Mapping Council 1966).
Figure 4 – National Mapping Council diagram of April 1956 showing the imperial map scales recommended for mapping the different regions of Australia (Lambert 1956).
The January 1945 conference also believed 1 mile to 1 inch scale and 4 miles to 1 inch scale topographical maps were required for national mapping (Commonwealth Survey Committee and State Surveyors-General 1945). The 4 miles to 1 inch scale was later ratified by NMC Resolution 57 of 1948. That resolution also provided that outside specific, designated or most densely populated areas of the country 4 miles to 1 inch was considered a suitable scale (Lines 1992).
In the following years the scales at which Australia would be mapped were reviewed by the NMC. If mapping Australia at One inch was too immense a task in war-time, in peace-time it was totally impractical. It was more logical, as had been seen during World War 2, to map specific areas at specific scales. Refer to Figure 4, an NMC diagram showing the imperial map scales recommended for mapping the different regions of Australia (Lambert 1956). The question of map scales was finally resolved in 1959 with the NMC’s adoption of metric scales.
At NMC’s commencement, the Commonwealth Survey Committee was given a seat on the new Council. This seat was usually taken by the Director of Military Survey. However, in 1947, the CSC was re-organised. Its membership was expanded with the Commonwealth Surveyor-General (who was also Director of National Mapping) as chair. The CSC chair would recommend to the Minister for the Interior any actions necessary for the co-ordination of the mapping activities of Commonwealth departments. Soon after the formation of the NMC, its obligations grew to such an extent that its chair shouldered onerous responsibilities. Not only was he responsible as Director of National Mapping and as Commonwealth Surveyor-General but also as the Commonwealth’s Chief Property Officer. In 1947, to help address this situation, a Deputy was appointed to assist with the Director of National Mapping function. The new Deputy headed the National Mapping Section, Property and Survey Branch, Department of Interior. In 1951, the arrangement for the Commonwealth Surveyor-General to also be Director of National Mapping was terminated. The Deputy Director then became the Director of National Mapping and in that capacity chair of the NMC. Under this change, the Commonwealth Surveyor-General relinquished the chair of the NMC but remained a member of that Council. (The new arrangements provided the Commonwealth Surveyor-General some relief from his onerous work-load.)
Also in 1951, the National Mapping Section was renamed the National Mapping Office. This change saw the Office actively commence its part in the Australian geodetic survey (Ford 1979). The National Mapping Office worked co-operatively with RA Survey and State authorities with an initial aim to expand the geodetic network and to strengthen and unify existing survey control.
By 1951, Brown (1951) records that only twelve per cent of Australia was covered by topographic maps (equivalent in area to about the size of South Australia) even though most of these maps lacked height information. Map coverage with heights and contours at 1 mile to 1 inch and larger scales existed for just three per cent the country. Figure 3c, shows the map coverage as reported by the NMC in 1950, and is indicative of the coverage noted by Brown. In 1951, Major-General R. Ll. Brown C.B., O.B.E, F.H.I.C.S., Director-General Ordnance Survey of Great Britain, was invited to Australia to report to the Minister for the Department of the Army on specific terms of reference. These addressed RA Survey’s future work program and interaction with civilian agencies. While his main report of December 1951 deals with those issues, his Appendix G reflected Brown’s own views on key aspects of topographic mapping. Brown’s most relevant points were :
Since the war discussions on standardisation have taken place, and the scales of maps and charts affecting land operations have now been standardised for the armies of the United States, United Kingdom, and Canada. The object of this standardisation is to enable the mapping agencies of the three countries to supply the armed forces with the maps essential for military operations and to simplify map usage.
The standard scales agreed are all decimal scales.
The agreement designates these as the scales which shall be used by the three powers, and as the goal toward which they shall urge all other mapping agencies in order to facilitate future military mapping.
The standardisation of military mapping scales by these three North Atlantic powers cannot be without affect upon mapping in other parts of the world, and Australia will naturally wish to take this into account when considering her domestic mapping.
The Four-mile scale is so close to the 1/250 000 scale that for many practical purposes there is no difference. This is true also for many military purposes, but not all.
The territories in which she [Australia] may be interested are thus on the 1/250 000 scale. A change in Australia appears practicable, and if it is to be made, the sooner it is made the better.
These considerations have been put forward, more to prevent them from being overlooked when policy is discussed than to urge the intrinsic value of decimal scales.
This trend [to metric] may in the end prove irresistible, both because of the increasing disadvantage in a modern world of the lack of uniformity in this matter, and because no system other than the metric system has any chance of universal acceptance.
So far as mapping is concerned, Australia has as yet done little (as compared with older countries), that a change to decimal scales, and even the metre, would be a simple matter now compared with what it will be later when Australia is better mapped (Brown 1951).
Based on his own experience with national mapping in Great Britain, Brown noted that Australia needed to have a single mapping authority responsible for its national mapping activities. In 1954 in response to Brown’s report, the Commonwealth government established the Department of Interior as the responsible authority for topographic surveys and mapping in Australia. In addition, a standing Advisory Committee (later to be known as Advisory Committee on Commonwealth Mapping - ACOCM) was formed and the Commonwealth Survey Committee disbanded. The CSC’s former representative on the National Mapping Council, the Director of Military Survey, later became a member of the NMC in their own right. ACOCM’s members were : the Secretary, Department of Interior; the Secretary, Department of the Army; a nominee from the Institution of Surveyors, Australia. Its Executive Officer was the Director of National Mapping (who also chaired the NMC). ACOCM’s role was ‘the planning and co-ordination of Australia’s future geodetic and topographic surveys and mapping’.
Also in 1954, following establishment of the Southeast Asia Treaty Organization (SEATO) Australia was required to comply with that Treaty’s standardisation agreements. RA Survey noted both the need for this compliance (specifically in relation to map scales, units and symbology) and Brown’s comments relating to decimal scale. Accordingly, RA Survey informed ACOCM that they would like Australian mapping to so comply. With ACOCM having the appropriate administrative authority, all the issues relating to a national topographic mapping program for Australia could now be addressed. Consequently, the mid-1955 Recommended Plan of Mapping Operations emerged. This plan included a 1: 250 000 scale national topographic map series that incorporated the standardisation compliance requested by RA Survey. Commonwealth government approval came only months later.
From plan to reality
Two events in 1956 helped lay the foundation for a national, uniform, 1: 250 000 scale series of topographic maps, compiled predominantly from aerial photography. In May, the National Mapping Office in the Department of the Interior became the Division of National Mapping within the Department of National Development. In July, the Division of National Mapping received a budget allocation for mapping, essentially in the form of continuing payments to the States for their topographic mapping work that was suitable for use in the national mapping program.
The above two events started to address the three major problems that had forced peace time topographic map makers to compromise since the late 1940s: Firstly, how to rapidly provide comprehensive horizontal and vertical control for aerial photography that contained the topographic information needed over vast areas of Australia where little or no map control existed? Secondly, how best to extract the required information from controlled aerial photography to make the planimetric maps. Finally, even if the first two problems could be resolved, how was the required volume of printed maps to be produced? These problems were exacerbated, as mentioned in the introduction, by the severe lack of trained personnel after World War 2. The compromise had been the production of semi-controlled photo-mosaics (often referred to as photomaps). Based on aerial photography acquired post-war, approximately positioned but usable topographic information in photomap form had been produced quickly in sufficient quantity to meet demand. However, this outcome was at the cost of greatly reduced production of cartographic (line) maps.
Post-war aerial photography coverage was an on-going requirement that saw camera equipped Royal Australian Air Force aircraft operating in most States. In the period from June 1947 to June 1948, the RAAF was very active photographing over of one tenth of Australia with 40 000 photographs (Manning 1988). In March 1948, the RAAF aerial photography squadron was designated as 87 (Survey) Squadron. In 1953, however, the government directed that contracts should be let to commercial aerial survey companies for any aerial photography required by Commonwealth departments up to a limit of £120 000 per annum. The RAAF’s role in civilian mapping photographic acquisition subsequently ceased. National Mapping’s 1956 budget, mentioned above, included £120 000 for continued aerial photography acquisition. Thus, 1: 50 000 scale aerial photography supplied by the RAAF and civilian contractors was used for most of the R502 series mapping (Hocking 1987).
The establishment of the Division of National Mapping in 1956 allowed that Division to seek the resources necessary for a topographic mapping program. This funding helped to address but initially did not alleviate the previously mentioned topographic mapping problems nevertheless progress had commenced. With budget funding, however, came greater accountability and a realisation that mapping to meet national development priorities did not necessarily coincide with the current Defence or State mapping priorities. For national development needs mapping for matters such as the whereabouts of oil, gas, minerals, and water was required as well as interstate transport infrastructure routings.
Defence and State mapping priorities in populated coastal areas and in northern Australia generally did not assist with locating such resources. This lack of coincidence in mapping priorities between the various agencies was borne out in a 1958 Commonwealth government directive requiring National Mapping’s program be focussed on the sedimentary basins to assist with the search for hydrocarbons (Lines 1992).
Although the Advisory Committee on Commonwealth Mapping had agreed to adopt 1: 250 000 scale in mid-1955, it was not until 1956 that RA Survey adopted metric scales (Coulthard-Clark 2000). NMC agreement followed in 1959, whereby both Commonwealth and State mapping agencies adopted decimal scales (National Mapping Council 1972). As the Commonwealth had few 4 mile sheets to convert and the scale change was marginal, the conversion effort was minimal as Brown had forecast in 1951.
Along with the change to decimal scale, came the adoption of revised map symbology, a standardised edition numbering system (see Appendix A) and map sheet printing size. NMC agreement to an integrated set of national symbols (in line with SEATO standardisation agreements) came in 1958. Prior to this a British standard of 1906 had been used, and it formed the basis of the NMC Standard Topographic Map Symbols (STMS), first adopted by the NMC in 1948, amended in 1952 and published in February 1953.
The NMC Standard Topographic Map Symbols (STMS) revised to June 1962, recommended map symbols to be used in the production of topographic maps at medium and larger scales (National Mapping Council 1962). The June 1960, Royal Australian Survey Corps Manual of Map Specifications (published 1961 and as revised May 1962) also appears to have been a much used resource for the R502 map series (Royal Australian Survey Corps 1961).
While scale was decimalised, the existing 4 mile sheet lines were retained as was the use of the 10 000 yard grid and, although not critical at the time, foot interval contours. In 1933, RA Survey had adopted a transverse Mercator projection and a corresponding yard grid (Clarke 1858 spheroid) which covered the whole of Australia in 8 zones. Each zone was 5 degrees of longitude wide with a half degree of common overlap. This was a simple projection with no provision for a scale factor and each zone’s true origin at 34 degrees south latitude. This projection was used for the R502 map series until replaced in 1966 when the Australian Map Grid (AMG) was adopted. After adoption of the AMG, almost half the R502 maps were overprinted with the 10 000 metre grid in cyan.
Even though some of the specifications were still evolving, map production was moving ahead. Tennant Creek, the first sheet of National Mapping's COMMONWEALTH TOPOGRAPHIC SERIES 1: 253 440, was published in September 1958 in four colours, and depicted relief by 250 feet contours supplemented by hill-shading and spot heights. This was followed by black and white Provisional Editions, showing relief by spot heights alone. Forty-eight such sheets were published up to July 1961, when the series was superseded.
RA Survey had continued mapping after World War 2 at 4 miles to 1 inch scale (1: 253 440), some of the sheets being reprints of the war-time editions. Between 1948 and 1958 ten contoured, full-colour sheets were produced under the title AUSTRALIA 1: 253 440. Twelve black and white hachured sheets were also published between 1957 and 1961 under the title AUSTRALIA (PLANIMETRIC SERIES) 1: 253 440. Following the 1959 decision to move to decimal scale, National Mapping embarked on a Planimetric Series at 1: 250 000 scale and RA Survey a 1: 250 000 scale Topographic Series (Tyson 1965); both series contributing to the AUSTRALIA 1: 250 000, R502 program. Figure 5 summarises the medium scale topographic mapping scales used during the period 1907 to 1965.
Figure 5 – Australian medium scale topographic mapping scales used during the period 1907 to 1965 (after Tyson 1965).
The compilation methodology for the R502 series is illustrated in the photograph of a display panel of the time; refer Figures 6a & 6b. The four major production steps were: field work, horizontal control intensification, compilation and updating.
Field work: In the field, astronomical observations to determine position (astrofixes) were taken and other identifiable control from reliable sources confirmed and accepted. These control points provided absolute horizontal position. Lines (1992) recorded that some 2 540 astrofixes were used for the R502 mapping program. Figure 7 shows the location of all astrofixes that were observed to 1965. Heights came through use of barometric heighting techniques (Biddle undated), (Division of National Mapping, undated)(Figure 8). Hocking (1985) stated :…it is suggested that it would be desirable at least to obtain an astrofix in the vicinity of each intersection of 4 mile sheets, one in the vicinity of the centre of each 4 mile sheet, and one near each permanent feature such as homesteads, etc. Elsewhere it was recommended that when using the slotted template method for extending the map control, the best position for an astrofix depends on the airphoto coverage being used, with the observation point selected so as to appear on six photos, three in each run and as close as practicable to the centre of the common overlap.
The table at Appendix B shows that, in addition to the survey control established by RA Survey and National Mapping, each of the State mapping agencies of the time contributed as well as the following organisations:
Australian Gulf Oil Company Ltd
Delhi Australia Petroleum Pty Ltd
Department of Interior
Hydrographic Office, Royal Australian Navy
Snowy Mountains Hydro Electric Authority
Country Roads Board, Victoria
Weapons Research Establishment, Department of Supply
Western Australian Petroleum Pty Ltd (WAPET).
