Which Way North, Part IV - The Military Lensatic Compass

I'm going to kick off our formal evaluation of compass accuracy with the a design that has been in continuous use  for over 60 years and has seen use by millions of individuals.  It is perhaps the most tested compass design in history, with documented use in jungle, desert, woodland and arctic environments around the world.  It is tried and true and is one of my favorite compass designs.

It is the US Army's Model 1950 lensatic compass.

The M1950 compass is a design born of war.  It's predecessor, the M1938 lensatic compass, was developed and adopted just as WWII opened.  It was a good design that was easy to manufacture.  Equally important, the adoption of the M1938 compass allowed the Army to standardize land navigation training, simplify it and teach it to the millions of young men who were being drafted into the Army and Marines. The experiences of war taught the Army a few things about compass design.  First, it proved that the lensatic compass design was a good one.  It was accurate, reliable and versatile.  With its compass card graduated in both degrees and mils it was usable by the both infantry and artillery.  The military liked the basic design and stuck with it.

A Model 1938 (M1938) lensatic compass manufactured
 by the Superior Magneto Company of New York
Superior Magneto appears to have been the prime supplier of this
compass design during WWII

However, wartime experience also highlighted some shortcomings in the M1938 design.  It was somewhat fragile.  While not a toy, the M1938 was lightly built - just two stamped aluminum cups fitted together to form the compass bowl and lid.  It had no mechanism to lift the compass card off of the the pivot needle when the compass was closed.  A lot of compasses were damaged when the the tip of the pivot needle gouged or cracked the pivot jewel through rough handling.  But perhaps the biggest shortcoming of the M1938 compass is that it had no dampening mechanism. This meant that the compass card would swing wildly and would take a good number of seconds to settle down to the point where the Soldier could get an accurate reading.  There were some versions of the M1938, those manufactured by the W. E. Gurley Company (a leading manufacturer of surveying instruments), that included a needle lift mechanism that with practice could be used to brake or slow the compass card oscillations.  However, the vast majority of compasses were manufactured by the Superior Magneto Corporation and did not include this needle lift mechanism.

After WWII the Army incorporated induction dampening into the M1938 design.  Induction dampening is a beautifully simple concept.  It takes advantage of the inductive magnetic field generated between a swinging compass needle and a highly conductive but non-magnetic alloy like copper.  When a magnetic needle (or bar) is placed inside a cup made of copper and the needle swings (oscillates) that movement causes a slight magnetic eddy current to form.  When the needle swings to the left the eddy current pulls it to the right.  When it swings to the right the eddy current pulls it to the left.  The eddy current is self-canceling; as the needle oscillations decrease the eddy current strength decreases and very quickly the needle settles down and is aligned with magnetic north.  Simple, elegant and effective.

A late model M1938 compass with induction dampening.  This is
a transitional design, bridging the gap between the original M1938 compass
and the the M1950.  The white colored compass bowl is actually
a copper cup that forms part of the induction dampening system.
This compass was made in December 1950 by the
Marine Compass Company out of Pembroke, Massachusetts.

However, by the late 1940s the Army decided it was time for a whole new design.  The Army took the best functional elements of the M1938 compass - the lensatic sighting design and the combined degree and mil scales on the compass card - added induction dampening, a needle lift device, a much larger sighting lens and a larger thumb loop and placed it all in a beefed-up waterproof aluminum housing.  The resulting compass was designated the M1950 Lensatic Compass.  It is a rugged, versatile device that has remained in use with the US military for over 60 years, pretty much as originally designed.

M1950 Lensatic Compass
This particular compass was manufactured in February1953 by the
Marine Compass Company out of Pembroke, Massachusetts.   The
cloudy dial cover is the result of the plastic aging.  Remember, this compass
is almost 60 years old!

Same compass with the cover closed, showing the manufacturer and
manufacturing date.

Fast forward almost 60 years and the same compass design is still in use by the US military, and it doesn't look like they have plans to switch designs any time soon.

M1950 Lensatic Compass manufactured in 2010 by the Cammenga Corporation
out of Michigan.  This is a military issue compass that uses tritium inserts
for night time illumination.

The same compass with the cover closed.  At the time of this writing
Cammenga has been the sole supplier of lensatic compasses to
the US military for over 10 years.

Since 1950 this compass has been produced by a number of manufacturers, including the Marine Compass Company, Jay-Bee, Union Instrument, Cammenga and even Lionel (yes, the train people!).  However, it seems that the single biggest manufacturer of M1950 compasses was Stocker & Yale out of Massachusetts.  I don't have any specific production numbers for these compass manufacturers so my claim is based solely on personal observation.  Based on the compasses I was issued in the Army and what I see for sale on auction sites or in surplus stores it appears that Stocker & Yale had the highest production numbers.

Now, the US military doesn't just turn to a manufacturer and say "Make it!"  Like all things military there are clearly defined specifications.  It doesn't matter if you are building an aircraft carrier or a handheld compass, there must be clearly spelled out specifications!  So it is with the M1950 Lensatic Compass.  Today's compasses are built and tested in accordance with the DOD military performance specification known as MIL-PRF-10436N (Performance Specification, Compass, Magnetic, Unmounted, Lensatic, Luminous, 5 Degree and 20 Mil Graduations, With Carrying Case).

MIL-PRF_10436N
The document that spells out the design, construction,
performance and testing requirements for the
lensatic compass

(I should note here that the current specification does not use the 'M1950' designation.  I'm not sure when the US military dropped the designation, but for our purposes we'll continue to call it the M1950.  It's the same compass.)

The discussion of this performance document is important because the M1950 compass is the only US produced handheld compass I am aware of that is built to a specific performance specification, and is regularly evaluated against this performance specification by an outside agency.  If any test batch of compasses fails the evaluation the devices never make it out of the factory.  The M1950 is a purpose-built device designed to meet a clearly laid out specification not just for accuracy but for shock resistance, water resistance, illumination, thermal shock, durability and service life.  Manufacturers of other compasses may have their own internal standards (and many are quite good), but the M1950 is the only handheld compass you can buy that is designed to meet demanding military standards and is rigorously tested by an independent agency to ensure it meets those standards.

So just how good is the M1950 compass in the real world?  Pretty damned good!  The 58-year old example I show above that was made by the Marine Compass Co. is still perfectly serviceable and would probably meet all of today's performance specifications for accuracy and durability.  I have other examples in my collection that have clearly seen hard use, some with broken components or cracked dials, but they still provide reliable and accurate readings. The M1950 compass is a device that is hard to kill.

I believe that the key to the M1950's ruggedness is the fact that is it not a liquid dampened design.  Liquid dampening (where the compass needle or card is suspended in fluid to reduce oscillation) is very effective but is a more fragile design than the induction dampening used in the M1950.  With the liquid filled design the compass needle or card must be sealed inside a leak proof capsule*.  The problem is, compass manufacturers have not yet figured out how to make a leak proof capsule.  I have over 15 liquid filled compasses in my personal collection.  About half have air bubbles inside the capsule, a sure indicator that the fluid is leaking.

How accurate is the M1950 compass?  Every M1950 I've used (and after a 23 year Army career I've used a lot of them) has at least met, and many exceeded, the performance specification for accuracy.  Now this is where I need to come clean on my evaluation of the M1950.  It is not the most precise handheld compass available.  This compass' biggest design limitation is that the compass card is divided into only 5 degree increments; pretty coarse even for handheld use.

Compass card of the M1950 compass.
Note the inner degree ring (in red) laid out in 5 degree increments.  The outer
ring (in black) is set out on mils (6400 mils to a circle).  

This means that the average user, the common Soldier, can only discern and measure to half of that increment - 2.5 degrees.  Experienced users - mostly infantry and artillery Soldiers who use a compass regularly - can frequently get accurate readings to between 1.5 - 2.0 degrees. But to be realistic, 2.5 degrees is about as good as anyone can expect to get with this compass card layout.  The M1950 compass card design is a compromise.  The military needed to include a mils scale for use by the Field Artillery.  Mils offer more discreet division of the circle (a mil is 1/6400th of a circle), allowing for more precise azimuth determination - very important when you are calling in artillery strikes on distant targets.  To accommodate the mils scale it needed to be printed at the outer edge of the compass card, leaving less space to print the degrees scale.  This results in a coarse, less precise degree scale.

The military performance specification states that the compass must be accurate to within 40 mils.

"4.4.1.8 Magnetic performance and compass error.  The compass shall be placed in a horizontal position on a fixed point and by means of the sighting mechanism, the compass shall be sighted on three targets of known magnetic azimuths approximately 120 degrees apart.  With no remedial action by the operator, before, at, or after, a reading shall be taken at each target.  The difference between the known azimuths and readings taken is the compass error.  An error greater than 40 mils or failure of the compass to function correctly shall constitute failure of this test."

Since one degree = 17.8 mils, 40 mils is slightly less than 2.5 degrees.  Let's round up and call it 2.5.

I have tested my 2010 production Cammenga compass at a known azimuth station and found it to be accurate to just over 2 degrees when used in the handheld mode and sighting on targets up to 150 feet away.  This compass very easily meets the performance specification.

Before I wrap up this blog post I need to add that the M1950 compass was merely one component of a land navigation system that the Army developed and adopted at the end of WWII.  Along with the M1950 compass came dramatic changes in how the Army mapped the world, developing standardized maps with overprinted grids (the Military Grid Reference System) and plotting tools.  It was all designed to simplify land navigation for the common Soldier, and is was so successful that the methodology is still in use today.

The US Army's standardized land navigation 'system' included the M1950 compass,
standardized topographic maps, plotting tools and training materials.  It was an
extraordinarily successful program that is still used today.

Let's wrap this up.  Here is my bottom line - I consider the the M1950 compass to be the best general purpose handheld compass available.  It is a proven design that is built and tested to exacting standards.  They are readily available new or used to civilians and are one of the best examples of trickle-down military technology I've seen.  If you spend any time in the outdoors you need a compass.  You might as well get the best available.  Get a M1950 Lensatic Compass.

Thanks!

Brian

*One compass manufacturer, K&R out of Germany, claims to make a leak proof liquid capsule but I don't think they have been on the market long enough to have proven the claim.

The US National Map

Earlier this month the US Geological Survey (USGS) released their latest version of The National Map Viewer.

US National Map View of Maumee, Ohio

The same view of Maumee, Ohio with the aerial image
background turned on

The US National Map is not a map per se.  You can't ring up the USGS and say "Send me a copy of the National Map."  It doesn't exist as a single product.  The US National Map is a collection of digital geographic and geospatial data that, when brought together, forms the foundational map of the United States.  Here's how the USGS describes it:

"As one of the cornerstones of the U.S. Geological Survey's (USGS) National Geospatial Program, The National Map is a collaborative effort among the USGS and other Federal, State, and local partners to improve and deliver topographic information for the Nation. It has many uses ranging from recreation to scientific analysis to emergency response. The National Map is easily accessible for display on the Web, as products and services, and as downloadable data. The geographic information available from The National Mapincludes orthoimagery (aerial photographs), elevation, geographic names, hydrography, boundaries, transportation, structures, and land cover. Other types of geographic information can be added within the viewer or brought in with The National Map data into a Geographic Information System to create specific types of maps or map views. The National Map is a significant contribution to the National Spatial Data Infrastructure (NSDI) and currently is being transformed to better serve the geospatial community by providing high quality, integrated geospatial data and improved products and services including new generation digital topographic maps."


OK, like I said, it's a collection of digital geographic and geospatial data that forms the foundational map of the US.  Geeze, I think government bureaucrats get paid by the word.

Here is the USGS's introduction to the National Map program and the National Map Viewer:



The National Map Viewer is the USGS's on-line portal to all the data that makes up the National Map.

The Viewer is pretty good (if you are at all interested, it is built on ESRI's ArcGIS Server technology) and offers some neat functionality.  It will provide location information in a number of formats, including US National Grid coordinates, it has a pretty robust reverse geocoding feature (click on a building on the map and the map returns the street address for that location) and it will provide spot elevations from the national elevation dataset.  You can do area and distance measurements, add text and simple graphics and even add data from external sources like a GoogleEarth KML file or a web mapping service.  You can also bring up indexes for the USGS's standard map products like the US Topo series of maps and link to them for download as GeoPDF files.  For advanced users the Viewer offers some pretty good search and query builder functionality, so you can find specific data that is embedded in the data layers.

There are some shortcomings, however.  The print function is essentially useless and is perhaps THE major drawback of this Viewer.  About all it does is grab a screen shot of your viewer and dumps it to a PDF file.  The USGS needs to wake up and realize that people still want quality paper maps and with today's technology it should be easy to print a fully detailed paper map with things like a grid, scale indicator, geographic extents, legend, etc.

The Viewer also exhibits a common issue found in web-based maps - map content naming conventions can be pretty obtuse and downright confusing.  While the Viewer does pretty good with the base data layer naming conventions, when you start using advanced features like the Query Builder you start to interact directly with the database field names.  For example, if I'm building a query to identify all the wetlands in my county I'm presented with a list of 'Columns' (which are the database field names).  Those column names are confusing and don't mean anything to most humans.  We get to pick from selections named 'ATTRIBUTE' or 'OBJECTID' or 'SHAPE_Area'.  There is an easy solution to this - the GIS professional building this map can establish what are called 'field alias' names - a human-friendly nickname for each of the information fields.  ATTRIBUTE can be displayed as 'Wetland Attribute', OBJECTID can be displayed as 'Wetland ID' and SHAPE_Area can be displayed as 'Wetland Area'.  This naming convention issue usually reflects the fact that GIS professionals with little cartography experience compiled the data for use in the Viewer.  (If I seem to be nit-picking here it is because I build maps for a living using this same technology.  I know these are issues that are easy to fix and should have been taken care of before the Viewer was opened up to the public.)

These shortcomings aside, the National Map Viewer is pretty darned good.  I'd say the USGS gets a good solid 'B' for this effort.  If they'd improve the damned printing issue I'd give them an 'A'.

Brian

Which Way North - Evaluating the Compass

It's been a while since we looked at the merits and shortcomings of specific compass designs.  Over the past six months or so I've been testing and evaluating a number of handheld compasses from various manufacturers.  It has been something of a grail quest, searching for the perfect compass.  Along the way I've learned a lot about compass design, accuracy and usability.  In the next series of postings we'll discuss specific compasses and perhaps help you select a compass for your needs.  Not all of what I evaluated were modern compasses; I've included a few examples in this evaluation that were manufactured over 60 years ago and represent designs that go back over 100 years.

Before we get started let me state that there is no such thing as the perfect compass.  No one design can meet all needs.  The best approach in compass selection is to pick the design that best meets the needs of the job at hand.  If you are running an orienteering course you'll probably want to pick a compass specifically designed for that sport.  However, if you are doing serious backwoods land navigation you'll want a direct reading compass that can give accurate azimuths to within 1/2 of a degree.  On the other hand, if you are a geologist doing stratigraphic mapping you'll need a compass that will also allow you to measure the strike and dip of rock formations.  Always pick the tool that best suits the task at hand.

Over the next series of postings in the Which Way North series I'll evaluate specific compasses on the following criteria:

1. Basic Design - How good is the basic design of the compass, particularly if the compass was designed for a specific function?  How well does the design meet the stated goal?

2. Features - Are any added features (luminous markings, baseplate scale markings, built-in clinometers, etc.) useful and do they add to the functionality of the compass?

3. Execution - Did the manufacturer do a good job building the compass?

4. Usability - How easy is it to use the particular compass in the real world?

6. Accuracy - How accurate is the compass (in degrees) when used as it was designed and intended to be used?

Much of this evaluation will be subjective.  After all, it is my blog so I set the rules.  However, my subjective evaluation is based on over 40 years of compass use as a geologist, topographer and Army engineer officer.  I may be a bit subjective in my evaluation, but it is a well honed subjectivity.

Other things you should understand about my evaluation criteria are:

1. I value accuracy above all else.  If a compass is not accurate (within it's design parameters) then it is a piece of junk.  I don't care who made it or how expensive it was, if it ain't accurate it's junk.  I think it is important to understand how I evaluate accuracy.  I have access to an azimuth station where I test all my compasses for accuracy.  An azimuth station is a site where survey points have been established and the precise azimuths between points (in relation to true north) is established.  Each compass is checked against three points each roughly 90 degrees apart.  All are checked for handheld accuracy and if possible, supported accuracy when mounted on a jacob staff.  Each compass is tested three times in each mode and the magnetic azimuth results averaged.  The averaged result is then adjusted for local declination (as determined by NOAA) and checked against the known azimuths between each of the survey points.  The difference between the surveyed azimuth and the adjusted magnetic azimuth is the compass accuracy.

2. Ruggedness of design is next on my list of criteria.  A compass that is marketed for outdoor use should be able to withstand that use and deliver reliable and accurate service.  I'm not saying that we should expect to use a compass as a substitute hammer, but it is not unreasonable to expect a land navigation compass to easily withstand the normal bumps and shakes that come with being used out of doors.

3. Declination.  A lot of compasses have adjustable declination scales.  I do not consider the presence or absence of an adjustable declination scale of any particular importance.  In my opinion adjusting for declination on the compass gives a false sense of security.  There are far too many variables in the declination equation to allow it to be handled by a coarse declination scale built into a handheld compass.  However, an adjustable declination scale can be useful for another purpose - adjusting out any error built into a particular compass or compass design.

4. You rarely use the compass all by itself so consider it part of a land navigation kit.  This kit should also include maps of the area you are working in, a plotting scale and a notebook and pencil.  All my evaluations are done in consideration of the compass as part of this kit.

Also keep in mind that I didn't test every compass available.  My schedule (and wallet) won't allow that.  However, I did obtain the most common examples available from the major manufacturers like Silva, Suunto, Brunton, K&R and a few others.  If you have interest in a particular model or style let me know.  I may already have it on my list for evaluation or may be able to get an example to test.

So stay tuned for the plain truth on compasses!

Brian

Terrain Analysis

Last week I stumbled across this gem on YouTube -




It is a slightly dry film put out by the US Geological Survey in 1955 showing the modern (for the time) processes developed for natural resource analysis using aerial photography.

The guy narrating it sounds about as excited by his work as a dry goods salesman discussing the newest laundry soap.  Zzzzzzzzz...

But once past the dry narration I was interested by the methods demonstrated for geological, hydrological, soils and forestry analysis.  What struck me was that these were the precise methods we were taught at the Defense Mapping School as late as the early 1990s.  These photo analysis processes formed the basis for what we called Terrain Analysis, and in fact my job title for much of my Army career was Terrain Analysis Technician (MOS 215D).

This film approaches each type of analysis as an independent process - an end in itself.  We carried the analysis to the next level and merged the output from each of these four disciplines, mixed in some military-specific data like vehicle off-road capabilities, tossed in some road network analysis, some urban analysis and a pinch of weapon systems analysis and produced what we called a military terrain analysis.  Our products were usually delivered in the form of map overlays known as a combined obstacle study.  The process was very labor intensive and usually tightly focused on specific geographic areas like the Fulda Gap in Germany or the Koksan Bowl in Korea, natural movement corridors that had been used by armies for centuries.

Soldiers going into the Army's Terrain Analysis field received extensive training in field identification methods like geological and soils analysis, hydrological analysis and route engineering studies.  They were taught to observe, test and measure in the field using a variety of hands-on methods.  Next they moved to the classroom and were taught advanced aerial photo analysis techniques and applied their field knowledge to what they saw in the photos.  It was hours and hours of peering at photos through stereoscopes, analyzing texture, tone and pattens to develop a detailed analysis of the terrain and it's impacts on military operations.

Computers have taken on the burden of much of this analysis, and today you can feed a digital image into a sophisticated image analysis package like ERDAS Imagine and have it analyze huge swaths of territory in a small fraction of the time it took using the old manual methods shown in the film.  Still, it is fun to see how things were done in the good old days when men were men, hardhats were made out of aluminum and the science of aerial photo analysis found new applications in the civilian and military worlds.

Neatness Counts

Earlier we discussed the use of field notebooks and the lost art of field note taking.  I fear that neat, disciplined and structured field note taking is a lost art in the today's world of texting, instant messaging, and email.  Even in the engineering, surveying and topographic field (where I work) the use of field notebooks appears to have been brushed aside by smartphones, laptop computers, data collectors and the assorted electronic bric-a-brac that has come to dominate the field.  And yet - and yet - all this powerful technology still leaves us with critical information gaps.  The problem is not so much that people aren't writing stuff down, it is that they are writing it down in formats that are so very disjointed, disconnected and perishable.  An email here, a quick scribble on a random notepad there.  It gets lost or never gets integrated into the project file.  Months or years down the line engineers and maintenance personnel are left to wonder just where something was placed or how it was constructed because the story of that project was not properly documented.

Now, I'm not implying that the use of field notebooks will solve all of these problems.  Field notebooks are not a panacea for lousy project management.  My point is really that disciplined and structured note taking should be viewed as a key skill - and a requirement - for surveyors, engineers, topographers and other key staff.  Of course the ideal place to write all this down is in a field notebook, a field notebook that gets turned over to the organization, copied, indexed and integrated into a document management system at the completion of the project.

Neat, disciplined, complete and structured note taking.  Just what does that mean?

The disciplined and complete parts are easy.  Notes need to be made on any issue, topic, observation or discussion that directly impacts a project.  It is really nothing more than getting in the habit.  Get in the habit of having your notebook with you and writing stuff down.  Complete means get it all down.  Think of each record you create in the notebook as a miniature story - it needs to have a beginning, a middle and and end.  What you observed, when and where you observed it, what was important about it, who was there, what was agreed to, what conclusions were reached and, if necessary, sketches or diagrams that are key to the issue at hand.  Make it a complete story!

Neat and structured are two somewhat subjective concepts.  Everyone has their own style of organization and handwriting.  The important thing is to make it neat, legible and logical in structure.  Always remember that the intent is to make it easy for you and others in your organization to reference in the future.  How far into the future?  I routinely reference survey records for the airport I work at that are 60+ years old.  The neatness and structure (and completeness) of those records allow me to rely on them for locating structures and utilities that were abandoned and forgotten about decades ago.

I can only offer suggestions for the concepts of neatness and structure.  As I mentioned in my earlier post, field note taking used to be a topic taught in all beginning surveying and civil engineering courses.  Colleges, universities, government agencies (like the USGS and the USC&GS) and even individual companies used to have their own field note format requirements.  Some agencies, like the US Army Corps of Engineers, would even have entire bound books printed with pre-formatted pages.

A few agencies still provide specific field note standards.  Surprisingly, most are state departments of transportation (DOT).  For example, the Oregon DOT, provides specific guidance for field note structure.  Their Survey Field Note Standards (October 2006) provides very specific field note examples.  The same for the Montana DOT.  Their Survey Manual provides a chapter on sample notes that contractors are expected to follow.

But since this is my blog and I love old stuff, particularly old stuff that still has relevance, we're going to take a trip back to the 1950s.  A time when cars had carburetors, space travel was the stuff of science fiction and real men did surveys with optical theodolites and steel measuring tapes, and wrote everything down in hard bound notebooks.  A couple of professors at the University of Missouri put together a course in introductory surveying and field measuring.  A large part of the class involved proper field note recording.  This course was to serve as the foundation for all surveying and civil engineering instruction to come, so the instructors needed to make sure the students got started on the right foot with disciplined, accurate, structured and comprehensive field data recording.  The two professors, Clarence Bardsley and Ernest Carlton put together a gem of a book titled 'Surveyors Field Note Forms'.

Bardsley & Carlton, Surveyor's Field
Note Forms (3rd Ed.)

The book opens with a treatise on the importance of field notes and the necessity of being an accurate, error free, neat and complete note taker.

"Allow no items for the memory; all facts should be on the record."


"A good surveyor takes pride in the appearance of his notes.  A neat-appearing, well arranged set of field notes commands confidence and builds prestige in the surveyor."


"Field notes should be clear and convey only one possibly correct interpretation.  Descriptions and narrative matter should be in acceptable English.  Sketches should be drawn to approximate, or convenient, scales.  All numerals indicating distances, angles, or elevation should be carefully formed.  Particular care should be exercised in obtaining a logical order and sequence of all notes, for they should be absolutely clear and understandable to the student, other surveyors, computers*, or draftsmen."


The book then goes on to provide specific examples of problems and how the field notes should be formatted (click on any image to open it full-size):

Length of Pace Measurement

It was once common practice for surveyors to regularly measure and record their pace count over various types of terrain (flat, hilly, uphill, downhill, etc.).  Before accurate handheld measurement devices like GPS surveyors used pace count to do help them with tasks like finding property corner stakes or do rough fence line measurements.

Correcting for Horizontal Slope

Don't you just love the name 'Trachoma Hospital?

Using Rough Triangulation to Determine Distance

Although the equipment has improved, surveyors and engineers still use the principal of triangulation to determine inaccessible distances.

Sewer Stake-out

Construction stake-out, whether for sewers, buildings or roads, is still bread-and-butter work for surveyors.

Use of the Grade Rod

Field notes are for more than writing down numbers.  Often the engineer or surveyor needs to write down a description of how a particular piece of equipment was used, or a methodology that might need clarification.

Height of Object

Again, the equipment may have changed, but the procedure is still the same.

Determining Azimuth From True North

Using solar or star shots is still an accepted practice for determining the relationship to true north.

The point of the above is not really what is on the page as much as it is the legibility, accuracy and completeness of the data.  One hundred years from now, when Microsoft .pst files are lost to eternity, digital CAD files can't be opened and survey data collector files are corrupted beyond recall someone will still be able to pull a notebook like this one off the shelf, open it and clearly understand what the author wrote and was trying to convey.

Neatness does count.

As I was wrapping up this blog posting I asked Roberta (5th Grade Teacher of the Millennium) if kids in grade school still get penmanship lessons.  I was disappointed but not surprised to hear that, in her school system at least, penmanship has been sacrificed on the altar of computer skills.  Apparently the school system feels that there is not enough time to teach and practice penmanship, and since kid are all wired up to computers these days the time 'wasted' on penmanship is better put to teaching computer and 'keyboarding' skills.  How sad...

Brian


(*Note - In the 1950s the term 'computer' meant something completely different.  Back then a 'computer' was an individual who was responsible for doing final computations against the surveyor's field notes and applying statistical methods to determine the accuracy of the survey results.)

The Wilderness Route Finder

I grew up reading - devouring, really - the works of two great outdoor writers.  One was Brad Angier and the other was Calvin Rutstrum.  These two adventurers had been living the 'back to nature' lifestyle long before the backpacking craze hit America in the 1960s.  Both were prolific writers, turning out books and papers that extolled the wilderness lifestyle.  Angier's works were more philosophic - he fancied himself a modern day Thoreau and his books reflected that outlook.  Rutstrum, on the other hand, didn't just live the wilderness lifestyle, he actually worked in and made a living from the wilderness, primarily through guiding.  Rutstrum's advice was always more down to earth, more practical.

Some of Rutstrum's advice would cause modern day enviroweenies to fall over in a dead faint. For example, to deal with the biting insects that invariably got into your tent when camping in the north country Rutstrum recommended just tossing a DDT 'bomb' (spray canister) into the tent, zipping it up and letting the insecticide do its job.  Go off and do your chores and when you come back you'll have a bug-free tent to sleep peacefully in.  Keep in mind, however, that Rustrum's books were written from the late 1940s through the 1970s, so some procedures and 'best practices' are now out-dated and in many cases downright illegal.  Regardless, his books like 'New Way of the Wilderness' and 'Paradise Below Zero' are still considered classics of outdoor literature.

Another gem that Rutstrum wrote is 'The Wilderness Route Finder'.

My copy, purchased in the late1970s and well
thumbed

 I first came across this book over 30 years ago and read it cover to cover multiple times.  I believe it is the first broad application land navigation work written for the general public.  (The Army land navigation field manual, FM 21-26, pre-dates this work by several decades.  While an excellent work is targeted at military users.)  Rutstrum approached land navigation the way he approached so many things related to the outdoors - use what works.  He presents a broad range of techniques and discusses use of a number of pieces of equipment  that can assist in navigating the high latitudes where the magnetic compass becomes unreliable due to declination issues and local magnetism.

Obviously this book was written before GPS was even a gleam in the eye of senior military commanders, and many of the pieces of equipment Rutstrum discusses are out dated or simply not available anymore.  For example, cruiser compasses have not been made for decades and have now entered the status of collector's item.  However, some of the techniques he discusses, while at first glance seemingly archaic in the world of cell phones, wireless internet and GPS, are still valid and those serious about land navigation ought to give them a try.  For example, the concept of using a marine sextant to determine latitude is quite valid, and quality used sextants are available today for less than $400.  Equip one with a bubble horizon and bring along a quality quartz watch and you could even do reasonably accurate longitude determination.  Think of it as an exercise in confidence building.

The reader should be aware that Rutstrum wrote this book specifically for those navigating in the far north regions of the US and Canada.   There is little in this book about desert or tropical environments.  Rutstrum was also a man of his time and wrote like it.  Many of the explanations are a little wordy and personal pronouns are few and far between.  Keeping in mind these shortcomings, the book is still an undisputed classic and belongs on the shelf of anyone serious about learning land navigation.

Brian

Field Notebooks

Does anyone use field notebooks anymore?

In the olden days (like, up until the 1980s) field notebooks were a staple of the surveying, engineering, geology and natural sciences disciplines.  If you did any field work it got recorded for posterity in a field notebook.  Taking and maintaining field notes was not just an art, it was often a legal requirement, particularly in the surveying field; the entries that surveyors made in their field notebooks constituted the legal record of a survey and those notebooks often were turned in at the completion of a project to become part of the permanent record.

Field note taking and recording was usually part of the early coursework for beginning engineering & surveying students, and you were graded on the completeness, legibility and accuracy of your note taking.  Pencil only!  Erasures not allowed!  Mistakes had to be lined through and corrected notations added.  Our geology field classes stressed accurate structural and stratigraphic mapping along with proper representations of rock types and strike and dip measurements.  It was common during field classes for our professors to pull out an old weatherbeaten field notebook and refer to notes they had taken years before on the rock formations we were studying.

Virtually all of the big name engineering and survey supply companies sold field notebooks.  They were all pretty much the same - a hard bound book filled with blank lined pages (or alternating lined and graph) about 5" x 7".  The paper was 50% cotton rag content and usually treated to ensure archival stability and prevent wrinkling  from high humidity.  Most books included tables of conversion formulas, trig functions, curve tables, etc. in the last few tables; things now easily handled by a simple scientific calculator.  My suspicion is that there were only a few companies that actually produced these books and just did job orders for the big manufacturers.  There was a slight difference in quality from manufacturer to manufacturer, and the K & E and Post field books I've got in my collection are clearly a step above the average field book with sturdier covers and radiused page corners.

The US Army even got in on the act, and produced two styles of field books they classified as 'forms'  One, the DA Form 4446 - Level, Transit and General Survey Record Book was laid out like a generic notebook.  The other, DA Form 4196 - Horizontal Distance Book, was laid out specifically for recording traverses.  Both included a handy tear-out address label so that if found all someone had to do was tape the label to the outside of the book and drop it in a mailbox and the Army would pay the postage to get it back to its owner.  To this day I kick myself for not picking up more of these manuals when our Army surveyors abandoned them in favor of pre-printed recording forms.  They had boxes of them laying around new in the shrink wrap and I'm sure most went into the dumpster when they got tired of looking at them.

Thankfully, field notebooks are still available from engineering and forestry supply houses. Still in the same format and the same construction.  I guess when you hit on a winning formula there's no need to change.

But like so much in life, electronics got in the way.  With the arrival of total survey stations (theodolites), GPS-linked data collectors and computers running surveying and engineering-specific software the need for writing down project notes in a field notebook quickly disappeared.  While surveyors still use field notebooks to record things like the height of instrument or the serial number of the GPS receiver they are using on a particular project, the field notebook is no longer considered an indispensable item.

For much of my Army career I used field notebooks extensively, a practice carried over from my geology fieldwork days.  I was a sloppy note taker (see above), but I managed to get stuff into a logical and readable format.  Over the years I filled about half a dozen field notebooks with data collected on various projects in different parts of the world.  As I neared retirement I got caught up in the digital craze and abandoned notebooks for whatever was hot at that moment.  I've owned or used Pocket PCs, BlackBerrys, smart phones, iPhones, laptops, digital notebooks, you name it.  I've stored my notes in Borland Sidekick (anyone remember that piece of malware?), Windows Notes, Lotus Notes, Outlook, Outlook Express, iPhone Notes, MS Word, Wordstar, PC-Write, Open Office, and Google Docs.  Guess what?  Just about everything I stored in digital format is gone, gone, gone - unless I made a paper copy as back-up.  Roughly 10 years of meeting notes, field notes, observations, discussions, instructions from supervisors and directions to subordinates, everything gone.  Not because of some catastrophic event, but lost simply to the march of time, the changes in technology and the inevitable degrading of the storage media.

How many of you still have 5 1/4" or 3 1/2" floppies sitting around you can no longer read simply because you don't have a device capable of reading them?  Can your new DVD drive read that CD you burned back in 1999?  Ever wonder why TV shows shot in the 1970s and 80s look so funky?  It's not because of the bad hairdos or polyester leisure suits, but because so many of them were shot on videotape and the tape is starting to deteriorate.

Today the only way I can resurrect the record of my military career is through the written word put down on paper.  Thankfully I saved just about everything. I can't tell you the meetings I had in 2005, but I can tell you in some fair detail about the meetings I attended in 1985. In 2005 I trusted digital technology to store my data. In 1985 I trusted a notebook and a pencil.

About a year ago I realized I was missing key notes on some fairly heated meetings we had held with one of our business units at work.  I knew I had probably written my meeting notes and observations in a series of emails to my boss, but for the life of me I couldn't find the emails.  After about two days of searching on my computer and on our shared drives I remembered that I had done an email backup and clean-out about six months earlier and that my backed up files were on a USB drive - a drive I knew I had misplaced a few weeks before!  At that point I resolved to start writing things down and decided to start using field notebooks again.

As I've gotten back into the process of writing things down archivally I've been surprised at how my seemingly random scribblings begin to come together to tell the tale of the projects, events or items of interest that impact my life.  I can flip through the pages of my notebook and clearly view the progress of projects and issues I'm tracking.  I can go back to meetings held months ago to remind myself precisely what was said and agreed to. When an engineer has a question about the invert of a pipe we measured three months ago I can show him my original field notes. Sure, all of this information can be stored digitally (and most of it is), but my experience shows that I can't put much stock in that digital data being available five years from now. In five years I'm pretty sure my notebook will be sitting on my shelf ready to be opened and referenced.

If it's important, write it down on paper!


Brian