During the 1851 Great Exhibition, which welcomed over six million, visitors it was realised that London cabbies were incapable of finding their way around London, and so The Knowledge was born.
Before that time Edward Mogg had produced was then regarded as the definitive guide to the Capital in a series of guides for visitors: London: Edward Mogg’s Strangers Guide to London.
Measuring Victorian London: Mogg’s cab fare book
1. Mogg’s Postal-District and Cab-Fare Map, 1859. Drawn by Edward Mogg, lithographed by C. Whittingham, London, published by William Mogg, London. 532 x 720 mm (Paul Dobraszczyk)
Running parallel to the development of fare books in the nineteenth century (like Mogg’s Ten Thousand Cab Fares) was the publication of what might be described as ‘at a glance’ information: that is, information contained on one sheet of paper in the form of comprehensive fare tables or maps. Books of fares, no matter how well designed, were clearly problematic to use, whether carried in a pocket or consulted in a cab: in a book format information could never be ascertained ‘at a glance’; pages had to be turned, indexes consulted, destinations and cab stands memorised.
2. Detail of Mogg’s Cab-Fare map, 1859
Mogg attempted to address this problem with his series of Postal-District and Cab-Fare maps (1 & 2), drawn by his brother Edward. Superimposed onto a conventional topographic map of London are grid squares at half-mile intervals, labels of the postal districts, and the four-mile radius from Charing Cross (shown as a dark circle) that marked the transition from a sixpence to a shilling fare per mile. In addition, referencing aids are included around the edges of the map: letters along the top and bottom; numbers on the sides. In the 33-page index that accompanied the map and listed 3,000 places, readers were instructed on how use the map (3): first, they were to locate their required destination in the index, and, second, to memorise the letter and figure of the square required (4). By then consulting the map and matching the letter and figure to those given around its edges, the user could find the required place ‘instantly’.
3. Explanation of how to use Mogg’s map
4. Index to Mogg’s Cab-Fare map
Whether cab maps were indeed ‘useful’ to visitors to London is difficult to ascertain. Punch, in 1851, provided its own satirical image of a map like Mogg’s being used (5). It showed two visitors to London engaged in a ‘topographic problem’, that is, trying to use a similar map to find their way from Seven Dials to the Eastern Counties Railway Station (now Liverpool Street), a distance of about 3 miles. With one visitor holding the map securely while the other squints up close at the obviously far too detailed map to try and measure the distance with his fingers, Punch mocks the optimistic claims publishers like Mogg generally made of their maps.
Main picture: Sherlock Holmes Museum