Wednesday, August 16, 2023

Review: Manual of Field Sketching and Reconnaissance

How do you make a map of an arbitrarily large area without the benefit of GPS or other modern instruments? And how do you do this while under fire from the enemy? The Manual of Field Sketching and Reconnaissance, published in 1903, covers precisely this topic.

The recommended answer, by the way, involves setting an appropriate scale (say, 1 inch = 1 mile), methodically measuring and plotting out a number of points in that scale (say, walking 1.5 miles and then drawing the corresponding a 1.5 inch line on your paper), and then using these established points to triangulate other notable locations on your map. Finally, add symbols, text and perhaps contour lines and bam! you've got a map!

Admittedly, this process isn't quite as easy as I'm suggesting above. But, it is certainly a learn-able skill, and requires only the minimum of technology to accomplish.

Because the manual is written for the creation of maps and reports during war time, there's an emphasis on being creative and improvising. For example, rather than measure distances using precise instruments like chains, a number of other option are given:

The straight lines, called traverse lines, are measured with a chain or tape, or by pacing, or by cyclometer, pedometer, perambulator, or by time, or by estimation.

If if you're performing recon of an area by horseback, then this advice would be especially handy:

As regards the measurement of distances when sketching on horseback, it used to be the custom to count the horse's paces. But this system has great disadvantages; it is vexatious and laborious, and the resulting preoccupation of mind prevents the sketcher from looking about him and studying the country through which he rides. By far the best way is to measure distance by time.
  Allow 12 miles an hour for a canter,
        8  „                 „ trot, 
        4  „                 „ walk,
under normal conditions.*

Then draw a scale of minutes at the trot on the ruler.
Thus: Scale of sketch 2 inches to 1 mile,—
In one minute at a trot 8/60 mile, or 235 yards, will have been covered, 235 yards at 2 inches to 1 mile = .27 inch.

One aspect of the text which I found unexpectedly eye-opening was the chapter on scale. As a map reader, scale isn't something I'd given a whole lot of thought to; it just is what it is. But, as a map creator, the choice of scale has far reaching implications. Say you have a 10 by 10 mile area you'd like to map. If you're working with an 8½x11 inch sheet of paper, then a 1 inch per mile scale simply won't fit on the page. The scale you choose directly reflects how much detail you can capture on a map. I'm so used to digital maps where you can zoom in and out, effectively morphing the scale at will, that the idea of picking one scale to work in is truly an exercise in balancing competing needs.

I found the section on night time sketching to be enlightening. In the early 1900's the flashlight would be considered futuristic tech; invented but hardly practical. Yet, I was surprised to learn that luminous paint was available. The idea of marking compass points with this type of paint seems modern, and yet, this is precisely what the manual recommends. This theme of finding seemingly modern map and navigational concepts in the text was common. For example, the role of countour lines or how your location on the globe impacts your magnetic North, are just two small examples of this phenomena. While the language of this text seems dated at times, so many of the concepts are as true today as they were back then.

Overall, I found the field manual to be a fascinating read. There's practical advice here that's useful in situations when you don't have access to a GPS or Google. But more than that, the book is a window into the mind of the map maker. This volume contains an impressive number of reproduced maps. These show, even under trying circumstances, the kind of high quality creations that can be authored when soldiers in the field combine skill, improvisation and artistry that's called for in this text.

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