DOI: 10.14714/CP101.1831

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Clock and Compass: How John Byron Plato Gave Farmers a Real Address

Review of Clock and Compass: How John Byron Plato Gave Farmers a Real Address


By Mark Monmonier

University of Iowa Press, 2022

181 pages

Paperback: $19.95, ISBN 978-1-60938-821-8

Review by: Matthew Hampton, Oregon Metro

Mark Monmonier’s Clock and Compass: How John Byron Plato Gave Farmers a Real Address is a comprehensive and engaging look at the life and work of John Byron Plato, an early twentieth-century American cartographer and entrepreneur who revolutionized rural addressing in the United States. The book provides a detailed account of Plato’s innovative Clock System, a geographic addressing scheme that gave rural residents a physical address like their urban counterparts. This system, an early form of georeferencing, was based on a location’s distance and radial direction from a nearby town or village, and contrasted with the ofttimes-cryptic Rural Free Delivery (RFD) system used by the post office at the time. RFD routes were designed to optimize a letter-carrier’s rounds, while the Clock System centralized location finding.

The narrative of Clock and Compass is rich in detail and is driven by Monmonier’s expert knowledge of cartography, as well as his ability to tell an interesting story. The book is filled with interesting anecdotes, maps, and diagrams that serve to illustrate the key concepts of Plato’s Clock System and provide readers with a deeper understanding of its impact on rural addressing. The book begins with an overview of Plato’s early life and career—a life characterized by a series of entrepreneurial ventures that included a lumber dealership specializing in veneers, a teaching position, and a manufacturing business specializing in a safety horse hitch for which he held three patents. Despite his varied professional background, Plato is best known for his invention of the Clock System, which was born out of a personal experience he had as a dairy farmer in Colorado.

As the story goes, a customer wishing to purchase one of Plato’s Guernsey cows set up an appointment but after looking for hours, failed to find the location of the farm and instead sent him a polite apology that they didn’t have time to follow the postal worker the next day. This locational quandry provided Plato an “a-ha moment,” and he came up with the idea for the Clock System for rural addressing. Under this system, land was partitioned into districts separated by twelve evenly spaced lines radiating outward from a well known place, such as a town center. Each district was numbered in clockwise succession from one to twelve, and subdivided into one-mile zones radiating outward from the local center. Any rural place was identified by its direction (hour) and (crow flight) distance from that local center.

Much of Plato’s ingeniousness is reflected in the business structure he developed to implement his system, which involved securing the confidence of rural residents and local businesses, and employing energetic local school kids to do much of the labor. Children would scout locations for Plato, while he worked to earn endorsements from local farm bureaus and other respected sources. These endorsements, along with the promise of being more easily found, induced residents to agree to having address signs hung on their fences. While the children did the work of placing the signs, Plato got local businesses to buy into the system by offering them opportunities to advertise on his free and widely available address maps.

Plato continued to use his “lost sale” narrative over the years to promote his publications and subsequent business creating rural indexes in Colorado, New York, and Ohio. It was in Ohio that Plato experienced the rough shoulder of the Great Depression—forced to declare bankruptcy, he lost his company and had his property repossessed. Plato eventually moved to Washington, DC, and found work at Census Bureau.

It is significant to note that in 1936, six years after Plato’s patent expired, a new unrelated group of investors saw an opportunity and re-worked his system—switching from a clock to a compass—and re-mapped the counties in which he had previously created markets. This form of spatial indexing was very popular until the pervasiveness of the telephone and its printed “telephone guide” helped to supplant the investment in printing individual rural index maps. Monmonier, though, leaves no doubt in the reader’s mind that it was John Byron Plato who fathered rural index mapping, and that his conceptual fortitude helped to illustrate the need humans have to find locations.

Among the highlights of Clock and Compass are the numerous maps and diagrams included throughout the book. These visual aids help to illustrate the key concepts of Plato’s Clock System and provide readers with a deeper understanding of its impact on rural addressing. Additionally, the book includes a wealth of notes and references that will be of interest to historians, cartographers, and anyone interested in the history of rural addressing. This is the second book by Monmonier that mentions John Byron Plato, and readers interested in more background information should read Patents and Cartographic Inventions (2017) as well (reviewed in CP 90).

The idea of a location framework that measures distances from a central location is regularly used in modern digital form of a dynamically segmented network. While I doubt we can ascribe that particular idea to John Byron Plato, we can, thanks to the documentation of his life and work in this field provided by Mark Monmonier, recognize Plato’s important place in the history of rural addressing.

In conclusion, Clock and Compass: How John Byron Plato Gave Farmers a Real Address is a well-written and informative book that provides an in-depth look at the life and work of one of the pioneers of rural addressing in the United States. It is filled with diagrams, maps and reproductions showing the development and spread of Plato’s locational ingenuity. This book is a must-read for anyone interested in the history of cartography, geographic information systems, or rural indexing.