The Atlantic Neptune Online: Electronic access to historical maps for researchers and collectors

Digital libraries are now being assembled to enable online access to the collections of rare historical maps stored in libraries and archives around the world. By combining image scanning techniques with the ever-increasing efficiency of network communications, curators of map repositories can now consider a digital model for delivering information to researchers and collectors.; This research examines current technologies being applied to digital conversion, map referencing and online delivery of historical maps. A selection of digital library projects now under way are compared, and a method for digital historical-map library construction using commercially available software is presented in prototype format. The availability of multi-resolution online display software, now in use at the Library of Congress, is identified as a significant development for online delivery of historical maps. However, since few libraries have the required technical or financial resources to implement this solution, an alternative method for digital map library construction is described in this report.; The Atlantic Neptune Online prototype is presented as an online reference to a selection of nautical charts from J. F. W. DesBarres' 18{dollar}rmsp{lcub}th{rcub}{dollar} Century atlas, the Atlantic Neptune. Scanning software, digital image processing methods and geographic information system (GIS) tools are used to construct the prototype. The design and construction methods used for each component of the Atlantic Neptune Online are given.; Many of the first generation digital map library projects now in progress, are being developed from low resolution source images which are of limited use to researchers and collectors. The use of high resolution scanners and multi-resolution software is strongly recommended for those researchers and collectors who require the smallest map detail to be reproduced on screen. A geographically-referenced indexing system is also needed to accurately define the boundaries of each map or chart in the library.