Category Archives: mapping

Mapping

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Mapping
I was going through some of my books and manuals this morning and stumbled across this old favorite.  I spent a few minutes flipping through the pages and was reminded just what an absolute gem of a book it is.  I consider it a minor classic.
As the author David Greenhood states in the first line of the Introduction, “This book has been written to be read rather than studied.”
 
And so it should.  This is not a textbook or a reference, it is an educated man’s introduction to the concepts of topographic mapping.  Authored by somebody who had a deep understanding of the subject and knew how to write for general audiences, it is readable, enjoyable and instructive.
Although this book was first published in 1944 and incrementally updated through 1964 it gives up little to the back half of the 20th century because it focuses on concepts rather than gizmos.  There’s not a word or hint of satellite navigation, space-based imagery platforms, world-wide datums and coordinate systems or computer-based mapping.
Greenhood’s discussions on things like scale, perspective, contouring, projections and map compilation are some of the best and easiest to grasp that I’ve ever encountered.  Greenhood’s coverage of these concepts stand the test of time because they don’t change over time.  Scale is scale, perspective is perspective, whether you are looking at a paper map or a computer screen.
Some of the topics seem quaint, like how to properly sharpen a pencil or how to select the correct paper for drawing a map, but the discussions are charming and still somewhat useful in today’s world.  Most of the referenced publications are out of date and long out of print, but it’s important to note that many of Greenhood’s references were classics in their own right and are themselves worth hunting down and reading.
One of the real strengths of this book are the illustrations.  Most of the illustrations are hand drawn and they remind us that a talented illustrator can easily convey complex information in  ways photographs can’t.  The illustrations are expertly integrated with the text and provide support and reinforcement to the topics under discussion precisely when and where needed.
I bought my copy of Mapping in 1982 at the bookstore in the Smithsonian Museum of American History in Washington, DC.  It has been paged through and referenced so many times the binding is starting to come loose.  This morning I jumped out to Amazon to see if the book was still available.  I’m pleased to see it is still published by the University of Chicago Press, but the price is an eye-bleeding $32.50 – quite a lot for a trade paperback.  However, copies are available from used booksellers for very reasonable prices.  I grabbed a new-condition copy from an Amazon partner bookseller for $6.95, not much more than the $5.50 I paid for my current copy back in 1982.
If you are at all interested in mapping, or want to introduce the concepts of mapping to a young audience this book is an excellent start.  I’ve read a lot of books on mapping down through the decades and this is the best single volume introduction to the field I’ve ever read.
Brian

 

Old School Map Making

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I was wandering through YouTube at work today (shhhhh…) and stumbled on this neat old Army training film that describes the steps required to make a paper topographic map, circa 1973. The steps in this movie really didn’t change for about 60 years, from the late 1920s to around 1990 or so.  In fact, not a whole lot if the equipment changed, either. Sure, there were a few improvements here and there – better materials, more accurate surveying equipment and better aerial photography cameras – but the basic steps remained pretty much unchanged.  Of course today it is all different; digital satellite imagery, GPS, LiDAR and desktop computers have fundamentally changed the mapping profession. But for now let’s celebrate the old ways, when men were men, theodolites didn’t have any electronic components and cartographers wore ties while they worked at their light tables.  This movie (broken into three parts by YouTube) was filmed mostly at the old Defense Mapping School at Fort Belvior, VA: Part I:

Part II.  Now, part II is interesting because I swear the soldier who is shown working at 5:40 is an old friend, Norm Price.  I first met Norm at Fort Lewis in in 1987.  Norm had been a Cartographic Technician warrant officer who recently converted to the new Terrain Analysis Technican field (MOS 215D) just before I met him.  If I remember correctly he entered the Army in the late 60’s, so it is entirely possible for young Specialist Price to have appeared in this film:

And Part III:

Enjoy!

– Brian

Gas Station Maps

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In olden times, like back in the 1960s, you could pull into any gas station in the US and grab a free road map.  These maps were designed for one purpose – to show the motorist how to get from where he was to where he wanted to be.  The maps were part advertising and part incentive.  The idea was to encourage travel by automobile.  The more you traveled the more gas you burned.

The idea of the free road map was born back in the early 1900s when automobile companies like Ford were involved in a major push to get the state and federal governments to expand and improve roads throughout the country.  Road conditions were simply awful back then and the thought was that better roads would encourage travel and commerce and, of course, spur automobile sales.  This led to the creation of the federal Bureau of Public Roads (later the Federal Highway Administration) and the first allocations of federal money for ongoing road construction and maintenance.

By illustration, one of Harry Truman’s standard campaign platforms when he was serving as a commissioner in Missouri, then Senator and ultimately as President was better roads.  He felt that no farmer in a rural area should have to travel more than two miles to find a paved road to get his crops to market.  The fact that two miles was viewed as a reasonable distance to have to haul products before finding a good road is reflective of the state of road construction in the rural areas of the country right up into the 1950s.

Well, if we’ve got all these good new roads how do we let people know about them?  Why the road map, of course!  Gasoline companies like Texaco, Shell, BP, Mobile, Standard Oil and many others viewed free road maps as part of the cost of doing business.  The gasoline companies didn’t do the map production themselves.  They farmed out the production to one of the few companies that specialized in making road maps.  Rand McNally, Gousha and General Drafting were the major players in this industry and they cranked out millions of maps between 1920 and 1970.

The other great thing about gas station road maps, besides being free, was that they were kept fairly current.  The compilation of these maps was a cooperative effort between the gasoline producers, the mapping companies and local, state and federal road and transportation bureaus.  Maps were updated and re-published as frequently as every year depending on the rate of road construction in a particular state.  Of course each gas company’s map was tailored to show company service stations and to proudly trumpet the superiority of their product over their competitor’s, but the actual map information tended to pretty consistent from company to company.

A side benefit from this program was the standardization of road map symbology.  Map makers realized we needed a common map language to depict things like primary roads, secondary roads, city boundaries, rivers and lakes and route symbols.  In very short order common symbols were standardized and used on all road maps, not just those handed out for free in gas stations.  Map symbols were a unifying language on the highways and byways of mid-20th century America.

In addition, millions of American school kids learned map reading from gas station road maps.   Schools regularly integrated map reading into the curriculum, and the map of choice was the good old gas station road map.  I think the peak of America’s map literacy came in the 1950s, when millions of American kids, eager to tell their parents where to go, took over the job of automobile navigation and honed their skills in route finding and trip planning with good old gas station maps.

In the 1950s we planned our journeys using a paper map and imagination.  Today we fire up the GPS and wait for it to tell us where to go.  I fear we have become map dummies.

Let’s take a trip back in time and see what it was like for a mapping company to keep up with changes to roads and road conditions.  Many would be surprised to learn that the methods used today are pretty much the same as we see in this video.  The equipment has changed – it’s all computerized now – but someone still has to drive the roads and note the changes.

– Brian

The NGS Does the IAGS

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My blog post last year about the Inter-American Geodetic Survey (IAGS) has has proven to be my most popular post, both in the number of pageviews and the number of comments.  Although I’m not burning up the internet, it is interesting to track where visitor’s interests lie.  Surprisingly, my blog post is also the #2 return on Google searches against the term ‘inter american geodetic survey’ (it seems that the acronym IAGS is in use by several completely unrelated organizations that generate a lot of traffic, so searches against that term won’t put my post anywhere near the top of the list).

I’m both elated and just a bit saddened by this outcome.  Elated that I seem to have hit on poorly covered yet important subject that I can contribute significantly to, yet saddened that the Army Corps of Engineers continues to ignore the very crucial contributions their topographic services and personnel made to the professions of mapping, surveying and geodesy.

When I wrote the blog about the IAGS I noted that there’s very little available information about the organization on the web and I tried to provide links to as much relevant info as I could find.  One of the sources I completely ignored was the excellent article about the IAGS that appeared in the March 1956 edition of the National Geographic Magazine.

March 1956 National Geographic article on the
IAGS.  Click here to read it.

Before the National Geographic gave up serious scholarly writing for feel good stories about baby seals and the therapeutic effects of tree hugging it actually published some darned good stories about geography, exploration, and adventure.  All three of these elements come together in this great story about the IAGS.  It is probably the best, and perhaps the only, popular account of the agency’s activities.  So, follow this link and read about the Men Who Measure the Earth.

Spy Satellites Declassified

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A KH-9 Hexagon Imagery Satellite.  The thing’s as big
as a Greyhound bus!

On 17 September 2011 the US declassified the KH series of satellites and their mission information.

Guess now I can tell my wife what I was doing for most of those 23 years I was in the Army.

What’s not discussed in the story, and I won’t go into too much detail until I know for sure it’s OK to discuss it in full, is the contribution these satellites made to the DoD’s world-wide mapping program.  Suffice to say, without these birds we would not have been able to accurately map the vast territories of the Soviet Union, Eastern Europe, China and all the other hostile places we thought we might have to go fight in.

More to follow…  Maybe.

Brian

The Software I Hate To Love

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In the Geospatial Engineering world there is one Big Dog software developer and a pack of miniature chihuahuas snapping at its heels.  The Big Dog is ESRI, developers of the ArcGIS suite of software products.

ESRI dominates the GIS (geospatial information systems) software field in the same way Microsoft dominates the computer operating system field – there are competitors but nobody even comes close to the market share that ESRI developed and has held for decades.

But unlike Microsoft, ESRI didn’t get to where it is by being predatory and imposing crushing licensing agreements on its clients.  ESRI got it’s market share the old fashioned way – by simply being the best product in the market for the target consumer group.  ArcGIS is the software product that moved the traditional discipline of topography out of the paper map and overlay era and into the computer-based, analysis driven discipline of Geospatial Engineering.

ESRI was started by Jack Dangermond, someone I refer to as a “Birkenstock wearin’, Volvo drivin’, granola crunchin’ hippie.”  In the late 1960s and early 70s, building on pioneer work that had been done on early GIS concepts and development in Canada (where the discipline of GIS got its start), Dangermond created a land cover analysis program called ArcInfo and released it as a commercial product in the early 1980s.

Early versions of ArcInfo were hindered by limited computer processing, storage and graphics capability.  Geospatial analysis is very much a visual discipline – you’re making maps, after all.  Early desktop hardware simply didn’t have the capability and capacity to bring the full visual mapping experience to the user.  Up through the mid 1990s only expensive Unix workstations could handle that level of processing.  This all changed around 1995 when desktop computing power started increasing exponentially with each new processor design while at the same time hardware prices dropped like a brick.  Almost overnight inexpensive desktop computers appeared that could easily handle the processing and graphics demands a software package like ArcInfo placed on them.  I was working as a GIS program manager for the US Army when this hardware revolution hit the field and watched as in less than two years inexpensive desktop PCs caught up with and then quickly surpassed the processing power of the Unix-based Sun, Silicon Graphics and HP  systems we had been relying on.  What also helped was Microsoft’s release of WindowsNT at about the same time.  Finally we had a serious network-ready enterprise operating system running on high capacity hardware that didn’t make our budget guys weep every time we said we needed to do an upgrade.

ArcInfo is the flagship product of the ESRI line and is extremely powerful software.  But in the 1980s ESRI realized that not everyone needed the processing power of ArcInfo (nor could they afford the nausea-inducing cost of an ArcInfo software license).  ESRI introduced a lightweight version of ArcInfo that included most of the visualization capability of the high end package but left out the heavyweight analysis and data development functionality.  They named it ArcView.  It was priced right – something small organizations and even individuals serious about GIS could afford (if I remember correctly the GSA schedule price for a single ArcView license ran around $600 in 2000).  The vast majority of today’s GIS professionals cut their teeth on ArcView.

But ESRI’s real contribution to the GIS profession is the development of data types that both support complex spatial analysis and can be shared across different software platforms.  It is Dangermond’s vision that GIS-based mapping and analysis solutions should not be a stovepipe, but a shared resource.  This drove ESRI to develop the concept of the geodatabase.  A geodatabase is a collection of data in a standard relational database management system (RDBMS) like Oracle or SQL Server, but the data has very unique spatial values (location in x, y and z coordinates) assigned to it.  This means that GIS software can leverage the spatial values to relate the data in a location context and other RDBMS-based software systems can easily share their information with the geodatabase.   The geodatabase only needs to store GIS-unique features and can pull and do analysis against associated data in another database.

ESRI also developed a version of the geodatabase that does not require a high powered relational database management system as it’s foundation.  About a decade ago ESRI introduced the concept of a file-based geodatabase designed for use by small organizations or groups.  The file geodatabase is a simple to create yet powerful and extremely flexible data format that brings most of the power of the relational database and complex data analysis to the desktop machine and the individual user.

But what does the future hold?  ESRI realized long ago that the Internet was the map content delivery vehicle of the future.  Paper maps were headed to obsolescence and what Jack Dangermond describes as the ‘rich web map’ would quickly become the geospatial data visualization and analysis tool of the future.  He’s right, but only very recently has web technology started to catch up with his vision.

For the better part of a decade it was possible to hire professional web developers to create some very nice web mapping applications built on ESRIs early web technology called ArcIMS.  The problem was that those applications were difficult to develop, difficult to maintain, and required a lot of heavy weight back-end web and database server technology.  Only large enterprises and governments could support the hardware, software, development and maintenance costs.  ESRI’s web solutions were very much limited by the immature web development technologies available at the time.  It is ESRI’s vision that even the average geospatial professional working for a small business or local government should be able to develop, launch and maintain high quality web maps that bring value to the organization they support.  ESRI started laying the groundwork for this vision back with their ArcGIS 9 series of software releases and the development of things like ArcGIS Server and the concept of Map Services.  Two years ago they released ArcGIS 10 that brought a lot of maturity to the concept of integrated and streamlined web mapping using the Microsoft Silverlight and Adobe Flex web development environments, and the launch of ArcGIS Online with its peek into the future concept of ‘cloud services’ for hosting GIS data, services and web maps.

At it’s recent worldwide user’s conference ESRI announced the pending release of ArcGIS 10.1 with better integrated and streamlined web development tools.  But ESRI also announced two new developments that are generating a lot of interest.  The first is the announcement that ESRI has partnered with Amazon.com to host robust, enterprise-level cloud services for GIS web mapping, data hosting and application development.  The idea is that an enterprise purchases an ArcGIS Server software license, passes that license over to Amazon and Amazon stands up and maintains the necessary database and web development environment for the enterprise.  This is a huge development because it can free the GIS group supporting the enterprise from the often onerous and restrictive shackles placed on it by their local IT department.

The other announcement was the pending release of the ArcGIS Online Organizational Account program.  The Organizational Account program appears to be targeted as smaller enterprises and groups that don’t have the money or need to purchase full-up cloud services like those offered by Amazon.  Under the Organizational Account concept an organization will be able to purchase data and web hosting services from ESRI on a subscription basis.  It is still a ‘cloud’ model, but on a smaller, more tailorable scale that should allow small organizations to enjoy most of the capabilities of a full-up ArcGIS Server implementation.

The last good thing I need to discuss is another little-known program released this year – the concept of ArcGIS for home or personal use.  ESRI’s software licensing fees have escalated to the point that the geospatial professional simply can’t afford a copy to use to keep his or her skills sharp.  I noted above that the GSA price for an ArcView license used to run about $600 – a bearable cost if you were serious about GIS.  However, the cost for an ArcView license now hovers around $1,600, far too much for even the serious home user.  This year ESRI announced the ArcGIS for Home Use program.  Anyone can purchase a 1-year license of ArcView for $100, a very reasonable price.  Not only does this $100 include on-line software training and support, but you also get a very extensive suite of add-on modules like 3D Analyst, Spatial Analyst and Geostatistical Analyst.  The total value of the software you get for your $100 subscription comes to over $10,000.  One hell of a deal.  Of course there are restrictions attached to this deal.  The intent of the home use program is just that – you can only use it at home.  You can also only use it for personal development/training purposes or non-profit use.  Still, like I said, it’s one hell of a deal.

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Now, it’s not all rainbows and unicorns when it comes to ArcGIS and ESRI’s position in the GIS world.  All this GIS goodness is of little use unless it’s leveraged in an environment with clearly defined professional standards.  Nor can you allow a professional discipline to be defined by a software application or be inexorably joined to a piece of software.  This is where ESRI’s has failed the geospatial community, and they have failed in ways they can’t even visualize from where they sit.

Here’s the reality: geospatial engineering is the discipline, the term geospatial information systems – GIS – merely describes the tools geospatial professionals use to do their job.  Where ESRI has failed is in using its industry position and influence to help clearly delineate the difference between the two.  As a result, far too many engineering professionals view geospatial professionals as little more than button pushing software monkeys, one step up from data entry clerks.

Part of the culture Jack Dangermond has fostered and progressed through ESRI is the idea that GIS is for everyone and nobody owns it.  What he is effectively saying is that GIS is the discipline; the tools and the software drive the field, not the other way around.

While community ownership is a noble goal, ESRI’s dominance of the field gives lie to that very philosophy.  Effectively, ESRI ‘owns’ GIS; it is by far the world’s largest GIS software developer.  It has either developed or successfully implemented most of the recognized spatial analysis processes in use today.  It’s data management features have driven the development of most of the spatial data standards in use today.  The vast majority of geospatial professionals worldwide learned their trade using ArcGIS.

What is lacking, however, is a clear and recognized definition of just what a geospatial professional is.  Dangermond is correct when he claims it’s not his role to define what a geospatial professional should be – that is the job of the geospatial field and industry as a whole.  But Dangermond has been the biggest catalyst in the geospatial world for the last 30 years.  He and the resources he commands through ESRI have been in the best position to cajole and coerce the private sector, academia and the government to establish the roles, practices and responsibilities that define Geospatial Engineering as a formal discipline.  He should have been the single biggest champion of the concept of Geospatial Engineering as a professional discipline.  Instead he’s been pretty much silent on the whole issue.

It is only in the last few years that the US Department of Labor developed a formal competency model for GIS (GIS, not Geospatial Engineering), and the GIS Professional Certification program is just starting to get its feet on the ground (after a disastrous grandfathering period that allowed perhaps hundreds of clearly unqualified individuals to get a GISP certificate and do damage to the reputation of the geospatial profession that may take years to overcome).  Great, but all this should have happened 20 years ago.

What this means is that Geospatial Engineering is not respected as a professional discipline.  I can tell you from long personal experience that geospatial professionals are looked down upon by other disciplines such as civil engineering and surveying, in large part because there are no testable and enforced standards that define us as a ‘profession’.  Guess what – they are right!

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Many readers are probably asking themselves “Huh?  What’s he getting at here?”  I guess I’d ask the same question myself if I didn’t understand the background issues.

I’ve been a topographer and geospatial engineer for over 30 years.  A few months back I laid out my initial arguments in a post titled In Praise of the Old Topographer.  In that post I made the argument that Geospatial Engineering is just a logical continuation of the older and much respected profession of Topographer.  I also outlined my argument that geospatial information systems, including ArcGIS, are merely the tools that the Geospatial Engineer uses to do his or her job.

With this post my goal was to identify one of the main culprits that is keeping Geospatial Engineering from fully maturing into a recognized profession, a profession with it’s own standards, roles and responsibilities.

ArcGIS is that culprit.  On the one hand we have extraordinarily capable software that is almost single handedly responsible for bringing the discipline into the computer age and is poised to bring it fully into the age of  world wide web.  On the other hand, ArcGIS and it’s parent company ESRI are almost single handedly responsible for holding the discipline back and keeping it from taking it’s rightful place as a profession on par with other engineering disciplines.

For these reasons ArcGIS is the software I hate to love.

Ohio Is Such a Mess

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“On the road above the Bell Company’s dock, Pennsylvania Route 68 invisibly changes to Ohio Route 38, and trees half hide some signs by the roadside.  The place could hardly be more anonymous.  Even someone familiar with the historical significance of this particular spot, who has traveled several thousand miles to find it, and whose eyes are flickering wildly from the narrow blacktop to the grassy verge between the road and river, can drive a couple of hundred yards past it before hitting the brakes.

The language of the signs is equally undemonstrative.  A stone marker carries a plaque headed “The Point of Beginning” that reads “1112 feet south of this spot was the point of beginning for surveying the public lands of the United States.  There on September 30th, 1785, Thomas Hutchins, first Geographer of the United States, began the Geographer’s Line of the Seven Ranges.”

There is nothing to suggest that it was here that the United States began to take physical shape, nothing to indicate that from here a grid was laid out across the land that would stretch west to the Pacific Ocean, and north to Canada, and south to the Mexican border, and would cover more than three million square miles, and would create a structure of land ownership unique in history…”

 – Andro Linklater, “Measuring America” 


In his wonderful book Measuring America, author Andro Linklater explains in detail just how it is that the concept of property ownership, and in particular the ownership of land, is the cornerstone of the American republic.  America was founded on the concept of property rights, and there is no greater realization of that concept than the idea that the common man can buy, hold and own land and that he, his family and his descendants will prosper and profit from the ownership and improvement of land.  The land does not belong to a government or a sovereign, but to the people.  It was a radical concept in 1776 and it is still very much a unique concept in the world today.

At the end of the Revolutionary War the weak federal government was cash poor but increasingly land rich.  Under the Articles of Confederation the federal government had no authority to raise revenue through taxation – that power was still retained by the individual states.  But the states were defaulting on their obligations to provide funding for the federal government.  The federal Army had not been paid for months and was on the brink of mutiny.  We had no navy to speak of.  Revolutionary War veterans were holding IOUs from the Continental Congress that were about to come due and our overseas creditors were demanding payment.  In desperation the federal government turned to the only asset it had available – land.

The Treaty of Paris that ended the Revolutionary War gave the new American nation control of a large tract of land west of the Ohio River in what is today southeastern Ohio.  This was really the only tangible asset the federal government owned that was not already claimed by one of the 13 states.  Almost in desperation, the Congress of the Confederation  hit on the idea of land sales as a way to support the struggling federal government.  The idea was simple – divide up the land and sell it for a dollar an acre. Cash only, no credit!

But how to divide it?  This new nation needed a land measurement and inventory system that was logical, easy to implement and resulted in land parcels that could be easily and quickly sold.  The resulting system, codified in the Land Ordinance of 1785, gave us what we know today as the township and range land survey system.  Conceptually is was simple – divide the land into six miles square sections (townships), then subdivide each township into one mile square sections, then further into quarter sections.  The initial unit of sale was a quarter section of 640 acres.

But where to start?  The Congress of the Confederation set up a committee to study the issue and appointed Thomas Hutchins, a noted military engineer and surveyor, as Geographer of the United States.  It was decided to start the land survey at the point where Pennsylvania’s northwestern boundary intersects the Ohio River.  This point became the Point of Beginning for all public land surveys in the United States.

So, on a blustery day in late September, 1785, Thomas Hutchins and his survey party walked down to the banks of the Ohio River, drove a stake in the ground, set their survey instruments up and began to lay out what became known as the Seven Ranges region of Ohio.

From this Point of Beginning Thomas Hutchins set in place the land survey system that would ultimately encompass 75% of the land mass of the United States, clearly establish and define private land ownership and set the stage for the explosive westward expansion of the US in the 19th century.  On September 30th, 1785 Thomas Hutchins literally drove the stake that established the geographic fabric upon which the United States was built.

Ohio was to be the proving grounds for the township and range survey system.  Like a lot of first tries at anything problems cropped up, adjustments were made and shortcuts were taken.  Part of the problem stemmed from the fact that much of the land in what we today call Ohio was subject to prior claim.  Large areas of  northern Ohio were ceded to Native Americans under various treaties.  Connecticut claimed a large region stretching from present day Sandusky, Ohio east to the Pennsylvania border.  Virginia claimed a large tract in the south to use to compensate her veterans.  Other bits and pieces here and there were set aside.  Ohio was a patchwork quilt of land claims, set-asides, treaty lands and private holdings.
Ohio Land Claims – 1800’s

But very quickly another series of problems popped up.  Congress was pressured by speculators to sell large chunks of land.  Congress saw this as a way to generate quick cash – sell land at a slight discount for immediate payment and let the speculators carry the cost of the land surveys.  The land speculators saw it as a road to riches – if they could sell fast.  But before any land could be sold it had to be surveyed and the surveys registered.  That meant the surveys needed to be done fast.  Accuracy be damned!

In the 18th century anyone with rudimentary math skills and who could afford a surveyor’s compass and chain could call themselves a surveyor, and many did.  Since surveyors at the time were paid by the mile the faster they worked the more they got paid.  This meant the surveys were sloppy and niceties like calculating the local differences between true north and magnetic north were either not done as often as required or simply not done at all.

As a result, a lot of Ohio’s township and range section lines take off at odd angles and don’t quite form square parcels.  Eventually the errors accumulated and corrections had to be made.  Often it was the simple expedient of offsetting a north-south range line at the start of the next township line.  Since roads in Ohio tended to follow the township and range section boundaries this led to the quirky (and often dangerous) tendency of country roads ending at a T-intersections for no apparent reason, then picking up again about 100 feet east or west of the end point.  These little jogs are a modern reflection of the corrections the surveyors were forced to build into their work over 200 years ago.

Other times the errors were so extreme that there was really no way to correct them and the government was just forced to incorporate the errors into the public record as-is:

The intersection of surveys for the Symmes Purchase, Virginia Military Reserve
and standard Public Land Survey areas.  There are about three different
interpretations of true north indicated by these township and range layouts!

So there you have it.  Ohio is a darned mess.  But a fascinating mess that leaves us the physical traces of the birth of the survey system that made westward expansion possible.

– Brian

The US National Map

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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

Terrain Analysis

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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

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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.)