Tactile Map. Tactile (Or Tactual) Maps Are Raised-Relief

ages having different elevations and textures. During the mid-twentieth century three-dimensional topographic relief models reproduced cheaply in plastic became pop- ular with sighted map readers, but the thermoform pro- cess had a more profound effect on tactile mapmaking. T Although institutional publishers had operated embossing equipment successfully, thermoforming enabled Tactile Map. Tactile (or tactual) maps are raised-relief individuals to reproduce large numbers of tactile maps spatial representations that are to visual maps as Braille relatively cheaply (fi g. 926). That led to more dispersed (a system of tactile writing with raised dots) is to visual and informal production of tactile maps, still for teach- text. Tactile maps enable visually impaired people to ac- ing geography but also increasingly for mobility. Those cess geographical information through touch. trends refl ected societal changes in post–World War II The few surviving European tactile maps from the Europe and America as the popularity of the automo- early nineteenth century and before are isolated ex- bile led to increased mobility, the development of road amples of one-off techniques, such as hand-carved and street signage, and the distribution of road maps. wooden models, embroidered maps, or collages glued Achieving comparably independent mobility for visually onto a backing (Eriksson 1998, 157–74). By the mid- impaired people required new ways of communicating nineteenth century, though, embossing machines de- spatial information. New programs training visually im- veloped in both Europe and America could employ paired veterans to use guide dogs and long white mo- engraved plates to emboss multiple copies of tactile pa- bility canes eventually led to university training courses per maps, most often for schools for visually impaired for mobility instructors. Mobility training also spread to children. Rival systems of tactile writing attracted more schools for visually impaired students, where there was attention than tactile maps during the nineteenth cen- a 1950s infl ux of children affected by RLF (retrolental tury, stimulating controversy that subsided only after fi broplasia, a visual impairment caused by oxygen-fed Braille became standard in the early 1900s. Embossing incubators introduced in the 1940s). Initially, tactile was still the method by which a Depression-era WPA maps with Braille labels seemed the most effi cient form (Works Progress Administration) project at the Perkins of geographical aids for mobility. School for the Blind in Massachusetts reproduced a During the 1960s academic cartographers, members loose-leaf atlas of 350 tactile historical maps between of an expanding fi eld in postwar Europe and America, 1936 and 1938. The primary use of tactile maps re- initiated serious scientifi c study of the design and use of mained teaching world and regional geography to visu- maps, both visual and tactile. Mobility and instructional ally impaired children. needs of visually impaired students coincided with read- However, tactile map reproduction experienced an- ily available thermoform technology to arouse interest in other burst of technological innovation in the mid- tactile maps. Rather than investigating visual perception, twentieth century. The fi rst thermoformed (or vacuum tactile map research focused on the nature of visual im- formed) maps were produced in Slovenia during the late pairment, especially tactual perception and spatial cogni- 1950s. Thermoforming equipment extracted air, creat- tion. In contrast to visual mapping, the mainly sighted ing a vacuum and pulling a heat-softened plastic sheet, cartographers of tactile maps were less likely than users usually PVC (polyvinyl chloride, a plastic commercial- to know which map features to include or how best to ized in America in the 1920s), onto a master model of a represent them. Another difference was that map reading tactile map. Reuse of the master yielded multiple copies through touch occurs sequentially as fi ngers encounter in durable plastic of raised relief maps with tactile im- raised images and depends upon memory to construct a Tactile Map 1481 Fig. 926. PORTION OF A LARGE-SCALE THERMO- Size of each sheet: 30 × 42 cm. From Thermoform Atlas of FORMED CITY PLAN OF AMSTERDAM. The map shows Amsterdam (Nijmegen, Netherlands: Bibliotheek Le Sage ten major routes, street names, water ways, and points of interest Broek [1995?]). Image courtesy of Jonathan Rowell. and is part of a ring-bound hardcover atlas with detachable sheets. complete picture (fi g. 927). Seeking to underpin design The fi rst strategic attempt to disseminate information with sound scientifi c principles, researchers employed and best practice was made through the Commission on experimental methods used in psychology and tested vi- Tactual and Low Vision Mapping, founded under the sually impaired participants. Investigations were primar- auspices of the International Cartographic Association ily concerned with defi ning discriminable symbol sets (ICA) in 1984. The commission later regrouped, with (Wiedel and Groves 1969) and learning more about map slightly broader objectives, as the Commission on Maps use tasks in the absence of vision (Nolan 1976). Design and Graphics for Blind and Partially Sighted People. guidelines for sizing and spacing symbols and Braille la- New techniques for printing raised images, such as bels were established. Kits for making tactile maps intro- foaming ink and microcapsule paper, were introduced duced in the 1970s promoted widespread consistent use in the 1980s. Microcapsule paper (also called swell or of recommended symbol sets (Edman 1992, 36; Bentzen capsule paper or, its trade names Minolta or Zy-Tex) 1997). They contained an instruction booklet and pre- was developed in Japan in the early 1980s. Thick paper, fabricated point, line, and area symbols in various mate- suitable for printing or photocopying, was impregnated rials (molded plastic, profi led wire, and different cloths), with temperature-sensitive capsules fi lled with alcohol. enabling designers to build personal thermoform masters After printing the paper was uniformly subjected to a within strict design specifi cations (fi g. 928). controlled heat source. Only areas beneath ink deposits 1482 Tactile Map reached a critical temperature and burst, thereby raising printed areas permanently in relief and rendering them tactile. Although subject to wear and occasionally diffi - cult to read, the resulting tactile images could be quickly and conveniently designed on a computer. Computer design and microcapsule reproduction increased the potential reach of tactile maps but made their quality and consistency more diffi cult to control. Computer-design options were many, but only a small subgroup of symbols was suitable for tactile perception. The wide range of map types and features needing rep- resentation far exceeded the suitable tactile symbols and precluded standardization. The more diffi cult it became to fi nd precise measures upon which to base tactile map design, the less important empirical studies and scientifi c enquiry became. Fig. 927. A CLIENT LOCATES HER DESTINATION BY Those engaged in the construction of tactile maps TOUCH ON THIS DUAL-IMAGE THERMOFORM MAP increasingly took a practice-led approach, with few at- OF BOSTON AND CAMBRIDGE. Printed on a plastic sheet at the scale of 1:30,480. Map designed by K. Lieneman (Bos- tempts to pool information. Although several authors ton: Howe Press of Perkins School for the Blind, [1980?]). published useful primers, guidelines, instruction manu- Size of the sheet: 44 × 60 cm. From Billie L. Bentzen, “Orien- als (Edman 1992; Bentzen 1997), and even a few em- tation Aids,” in Foundations of Orientation and Mobility, ed. pirical studies, academic curiosity about tactile mapping Richard L. Welsh and Bruce B. Blasch (New York: American essentially declined during the 1980s. Foundation for the Blind, 1980), 291–355, esp. 336. Permis- sion courtesy of Billie L. Bentzen. Tactile maps continued in demand, but the anticipated increase in user numbers did not materialize. Tactile map use remained concentrated in schools and did not become global. Despite some hotspots of tactile activ- ity (e.g., Eastern Europe, Scandinavia, South America), there was no offi cial tactile mapping in large parts of the world, particularly developing nations. One factor may have been generally declining emphasis on tactile information. For example, Braille literacy among visually impaired people dropped in the United States from 50 percent in the 1960s to an estimated 12 percent by 2007 as the trend toward inclusionary education re- duced the teaching of Braille in favor of other learning technologies (Brittain 2007). Research revived in the 1990s but shifted focus from standardizing tactile maps toward experimentation with auditory and haptic (a term encompassing the sensations of movement and force, as well as touch) technologies. Spatial information provided through other senses could supplement or replace tactile maps. One approach in- volved automatically generated oral descriptions (such as the Nomad, the Talking Tactile Tablet, or the Talking Kiosk) for use alongside standard tactile maps. Another Fig. 928. MAP FROM KIT OF MAPMAKING PARTS (NOT- sought to replace fi xed tactile graphics with dynamic TINGHAM, ENGLAND: BLIND MOBILITY RESEARCH multimodal devices, such as the haptic mouse, simulat- UNIT, [1975?]). A tactile map master created with a kit of ing the

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