Huw Thomas, Map Curator at The National Library of Wales takes part in our #LoveMaps Campaign.
Why cataloguing matters – Portolan Chart by Domenico Vigliarolo, 1592
This rather damaged chart is one of the greatest, and also one of the least well known, treasures of the National Map Collection.
It is a portolan chart, an early navigation chart drawn using compass directions and distances estimated by sailors on their travels. Unlike modern charts they are not based on systematic survey and are not based on any map projection. The oldest known portolan charts date from the 13th and 14th centuries; dating from 1592 this chart is quite a late example. Portolan charts were so important as navigational aids that they were considered to be state secrets by many European governments at the time.
The chart shows the East coast of the Americas and West coast of Europe and Africa and it was designed for navigating the Atlantic Ocean, prominently named on the chart as Mar Oceano. One of the interesting things about the chart is the relative accuracy achieved by the mapmaker based only on compass observations and dead reckoning.
So why does accurate cataloguing matter? When I first came across the catalogue record for this chart the author was given as Dom Domingo. Unfortunately, this incomplete rendering of the name meant that this chart was not identified as being the work of Vigliarolo and consequently left out of published bibliographies of his work. It took me a fair deal of research to discover who Dom Domingo actually was.
In order for scholars and other users to be able to access the wealth of resources held in a repository such as the National Library accurate catalogues are important, otherwise items are not found by researchers and their work is then incomplete. Cataloguing is one of those back office functions that most people don’t really think about, until they can’t find what they are looking for, but it is a vital part of our work.
Producing accurate records which help users find what they need is part of my job in which I take great pride, so next time you look at a catalogue record remember the work that went into producing it.
Why not subscribe to our blog posts and learn more about our work and collections? Please enter your email address in the right column.