Showing papers in "Cartographic Journal in 1975"

Some Objective Tests of the Legibility of Relief Maps

Abstract: The legibility of four different types of relief map (contours, contours with hill shading, layer tints and digital or spot height maps) was compared using 13 different map reading test questions administered to 179 subjects. Many of the questions showed large and statistically significant differences between the four types of map, but no single type of map was best for all purposes. The results demonstrate that the choice of an appropriate relief map has a very real effect on the map reader's performance, and that this choice must depend on the way the map is to be used.

The Map as a Communication System

Abstract: Only recently have cartographers devoted much attention to the study of the map as a communication system. It is now generally accepted that the study of how maps convey knowledge to a recipient, and therefore the study of the percipient as well as the process, are important areas of research. Various models of communication systems are analysed from the point of view of the inputs and transformations involved. The element of “noise”, characteristic of all systems, is examined as it relates to the map.The problem of assessing the amount of information included in a map and the efficiency with which geographical knowledge is evoked in a percipient is reviewed. Because a map is a two-dimensional presentation it is a very different form of communication from the one-dimensional linear forms that depend upon a temporal sequence, and consequently, the techniques of information theory are judged not to be directly applicable.

Experience and the Improvement of Cartographic Communication

Abstract: Both reader training and improved map design can be used to increase the communicative effectiveness of maps Tests with dot densities and circles indicate that either rescaling of symbols (design) or the allowance of some feedback (reader training) will result in more accurate median estimates The feedback approach, however, is associated with a greater dispersion in estimates, ie estimates are less clustered about the median When both the rescaling and feedback approaches are used, both the medians and dispersion are improved A different experiment, involving map comparisons, shows that a small amount of reader training can clarify the concept involved in that task and such clarification increases accuracy While both design modification and reader training induce improvements in map communication, these improvements are different in nature; the two approaches are not substitutes for one another but are complementary

R. K. Dawson's Proposal in 1836 for a Cadastral Survey of England and Wales

Abstract: In 1836, Lieutenant Robert Kearsley Dawson, organiser of the tithe commutation surveys, suggested that tithe maps should form the basis of a general survey of England and Wales on the Irish and Continental models. His idea was supported by the Tithe Commissioners but was strongly opposed, particularly on grounds of cost, by representatives of the landowning interest. This article reviews the debate on the combination of tithe surveys with a full cadastral survey. It was a debate which lasted for almost a year and ended with parliament deciding against Dawson's proposal. It was truly an opportunity lost.

A Kit for Making Raised Maps

Abstract: This article describes the development of a map making kit from which raised maps may be produced to aid blind people during travel. The method may be implemented at a local level, cheaply and without complicated machinery and utilises standardised symbols and procedures. The kit may be Used to produce single copy maps but is more likely to be used to produce map-masters from which copies may be vacuum-formed. It is suggested that symbols contained in the map-making kit should form a national standard in the United Kingdom.

Reduction of Linear Cartographic Data Based on Generation of Pseudo-Hyperbolae

Abstract: This paper presents the mathematical basis of a method for generalising linear cartographic data. The method is based on the transformation of the parameters of a digitised curve into a set of pseudo-hyperbolae such that no point lies outside a tube of given error tolerance e.The method has been programmed in the Fortran IV language for test purposes, and examples of the programs' results are given. The method should be of interest to those working in digital cartography who seek a method of data reduction which is both mathematically rigid and cartographically sensible.

Rapid digital mapping of coastal areas from LANDSAT

Abstract: The value of repeated imagery from satellite platforms can only be realised if coupled to rapid mapping systems. Techniques for producing rapid, user oriented maps from LANDSAT data are discussed, and examples derived from the mapping of the coastal and off-shore areas of eastern England.

Interactive Computer Cartography

Abstract: This paper describes interactive computer cartography which is a new approach in graphics construction. It briefly outlines some of the advantages of such a system. Both hardware configurations and software problems are identified and interactive output including shaded contour maps, two- and three-dimensional figures, world map projections, and three-dimensional surfaces are presented.

A Review of Design and Production Factors for the Ordnance Survey 1:50 000 Map Series

Abstract: The publication by the Ordnance Survey of the first 103 map sheets covering the southern half of Great Britain at 1:50 000 scale on 7th March 1974 was a conspicuous land mark in British cartographic history; firstly, because the tradition of 170 years of the One-inch to One mile scale had been broken and secondly, because such a large number of sheets were published simultaneously. This paper is an attempt to review some of the factors and problems in the design and production of the new series.

Cartographic Employers: A Survey of Recruitment and Attitudes

Abstract: This paper presents the results of a survey, made among cartographic employers, to examine the numbers, ages and qualifications of applicants for cartographic draughtsmen posts advertised in the national press. It also looks at the employers' attitudes to cartographic factors when assessing applicants for posts in their organisations.

Choosing of Colour Sequences for Reproduction in Monochrome Halftone

Abstract: Most coloured maps are not suitable for reproduction in black and white. If a map is to be used in both colour and monochrome, special attention must be given to the choice of colours so that they will still be distinguishable after being transformed into shades of a single colour. This problem is especially apparent in the representation of quantitative data, where the chosen area symbols must maintain their apparent relative value order in both colour and monochrome. This study was undertaken to establish several sets of colours that may be applied to maps which are intended to be used in both forms.