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Gephi Training (RMCLAS 2015)

Here are your data sets and links to the programs needed for today’s workshop:

Gephi

Palladio

Open Refine

Data Sets from Google Drive

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Tutorial on Juxtaposing Historical & Modern Images

Encouraged and inspired by my colleague Diana Montaño and Clayton Kauzlaric’s “Then & Again” project, I tried my hand at juxtaposing vintage, historical images onto modern ones. This approach, which visualizes physical changes over time, creates a powerful connection between the past and present of a particular place. In this tutorial, I will introduce the basic methodology for creating such an image using free, nearly universally-available tools. However, keep in mind that I am very much a novice at image retouching and editing, and feedback is much appreciated as I continue to improve this process and its end products.

Tools used:

Google Maps, Gimp 2.8, Microsoft Office Picture Manager, Microsoft Paint (seriously)

Steps:

1. Locate the historical image you wish to superimpose onto a modern one. For this example, I will be utilizing the fantastic digital archive of historical photographs of Mexico City created by Carlos Villasana, Juan Carlos Briones, and Rodrigo Hidalgo and located on their Facebook page, La ciudad de Mexico en el tiempo.

2. In this case, I selected a photograph of the iconic Palacio de Bellas Artes under construction during the first decades of the twentieth century (See below). Once one has decided on the historical image, it’s time to find its modern counterpart using Google Maps.

facebook step

3. Normally, one would need to open up a browser, go to the Google Maps site, and locate the approximate modern location of your historical object/building/event from the vintage photograph. Fortunately for those of us interested in the history of Mexico City, La ciudad de Mexico en el tiempo’s photo galleries include links directly to the Google Maps Street View corresponding to the vintage images. (See image below.)

google maps step

4. While viewing the modern location In Google Maps Street View, attempt to recreate the same angle and viewing distance as the original historical image. This can be frustrating as Street View may not provide the perfect perspective for the juxtaposition of the two images. This issue can be resolved by taking one’s own photograph at the physical location, but of course this is much more time-consuming and may require some travel. Once you have lined up your perspective in Street View as best as possible, it’s time to capture the images.

5. To capture the two images (historical & modern) for beginning the juxtaposition process, I’ll use one method for both images, although there are several ways to accomplish this step. For all images that cannot be right-clicked on and the image directly downloaded, you can use the “print screen” button on your keyboard. Move your mouse cursor away from the area of the image you want to capture and click the print screen button once. (See image below.)

keyboard print screen step

6. This single press of the button copies the entirety of your screen to be pasted into an image retouching program, which in this case, will be good old Microsoft Paint. Open up Paint and press the “paste” icon in the upper left corner of the program. (See image below.)

paste into paint step

7. Once you’ve hit this button, the captured image should be pasted into Paint for capture as a .jpeg file. Go to the drop down icon in the upper-left corner of the program and select “Save as” and then “JPEG picture.” (See image below.)

save as jpeg step

8. Do this process twice, once for the Street View image and one for the historical image, and save your new image files to a secure, familiar location on your hard drive (these steps can be skipped if you scanned and/or uploaded the image files to your hard drive yourself rather than from the web).

9. To edit these images for juxtaposition, we’ll need to crop them down a bit, so open these two image files with Microsoft Office Picture Manager or your image editor of choice. You can select which program to open these files with by right-clicking on the image file and selecting the program from the drop-down list. Once you’ve opened the image file, you’ll want to open up the option to “edit pictures” or its equivalent. (See image below.)

edit pictures step

10. To crop out the unwanted content surrounding the images, use the “crop” tool to edit the image. (See image below.)

crop step

11. Once this has been done, the perspective of the modern image should resemble the historical image as closely as possible. (See image below.)

cropped photo step

12. Now that we have our two images looking as similar as possible prior to juxtaposing, we are ready to open up the modern image first using our free image retouching program, GIMP. Certainly it is possible to retouch these photos using Adobe Photoshop, but money doesn’t grow on trees, and as an adjunct professor I’m always looking for ways to cut costs and instead utilize good quality freeware. Download and install GIMP (I’ll be using GIMP 2.8 here) from their official website.

13. Open the modern image pulled from Street View first, clicking on the “open” tab found under the “File” icon. (See image below.)

gimp open google maps image

14. Once you’ve successfully imported the image into GIMP, it should look like the image below. A multitude of tools are now at your disposal for image retouching, but first you need to import the historical image (See image below.)

gimp image opened in gimp

15. Instead of using “open” to bring in the historical image, go to “File,” select “Open as Layers,” and then the image file for the historical photograph. (See image below.)

gimp import 2nd image

16. Once you’ve imported the historical image in as a separate layer, your screen in GIMP should look like the image below. Now it’s time to manipulate the size and positioning of the historical image to match the modern image. (See image below.)

gimp 2nd image on screen

17. The first tool needed to manipulate the historical image is the “move” tool, located in the “toolbox” window on the left side of the program. This tool allows you to grab and relocate the positioning of the historical image atop the modern one. (See image below.)

gimp move 2nd image around

18. The other very important tool utilized for this process is the “scale” tool, also located in the left-hand toolbox window. This tool allows you to resize the proportions of the historical image to fit as precisely as possible on top of the proportions of the modern image. (See image below.)

gimp scale 2nd image

19. After you click the scale tool button, left click on the historical image to begin resizing it. A grid and resizing boxes will appear over the historical image, allowing you to either input the exact pixel dimensions of the image or to left click and hold on the resizing boxes at the edges of the image.(See image below.) I prefer to resize using the latter method, but be sure to hit the “scale” button on the pop-up box once your resizing process is complete. However, to “perfectly” line up the two images, you’ll need to use a combination of “scale,” “move,” and a particular image attribute explained in the next step.

gimp scale applied to 2nd image

20. The obvious challenge in lining these two images up and resizing/repositioning the historical image is the inability to see through the historical to the modern for accurate juxtaposition. This can be resolved by adjusting the “opacity” of the historical image via a slider bar located under the “Layers” window on the right side of the screen. (See image below.) By clicking/sliding this attribute’s value (0-100), the historical image becomes more transparent as the opacity value goes down. By doing this, the modern image can more easily be seen in the background, allowing for accurate resizing/positioning of the historical image.

gimp adjust opacity to 2nd image

21. As you reposition and resize your historical image, be sure to use visual reference points in your two images to ensure proper overlap. In this example, I used three specific visual markers. (See image below.)

gimp manuvering the image in place

22. Once the two images are properly juxtaposed on top of one another (see image below), it’s time to remove unwanted visuals from around the historical image in order to blend it into the modern landscape.

gimp lined up right

23. The final tool to be utilized is the “eraser” tool, located on the toolbox window on the left side of the program. (See image below.) Adjust your brush size, hardness, and opacity to remove the background from the historical image.

gimp erase 2nd layer

24. Carefully use the eraser tool to remove unwanted image materials around the historical image, careful not to go too quickly or with a brush that is too large to preserve the fine details at the edge of the building. (See image below.)

gimp start to erase 2nd image

25. This process of erasing and blending is where an artistic eye can be helpful, as the best means of blending in the street lamps, bushes, and pedestrians to appear as a natural part of this hybrid image is up to the editor. Use a medium-opacity eraser at the edges of the historical image to carefully blend it into the modern background to complete the juxtaposing process. (See image below.)

gimp eraser and opacity blending

26. You can now finalize your juxtaposed image by exporting it from the program. Click the file icon and select “export” from the drop down menu. You can select the file type (.png, .jpeg, etc.) and save location, click the export button, and you are done! (See image below.)

gimp export as png

27. These steps are a very crude, simple means of juxtaposing a historical and modern image, but I hope this tutorial provides a starting point for historical enthusiasts/image retouching novices to get started. I will continue to update and edit this tutorial as I learn more about fine tuning the process and improving the quality of the final product. I look forward to seeing your images!

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Teaching with Interactive Timelines via Tiki-Toki

After the wonderful but time-intensive relationship with Twitter in my world history surveys last semester, I decided to take a break from group projects and social media. This semester I gave my students a chance to create their own uncompromising, individual vision for a history project. Using the free, web-based software provided by Tiki-Toki, my 260+ students all “translated” research papers they completed earlier in the semester into digital, interactive timelines available for public consumption. As I stated in my post concerning the Twitter project, I am a huge believer in the capacity for these types of digital projects to empower, inspire, and educate students through the use of such a student-centered approach to learning. Through the creation of these timelines, students learn a greater appreciation of chronology and periodization, the art of constructing a historical narrative fit for “everyman” usage, and training in the usage of a powerful digital toolkit. I’m happy to say it was extremely difficult to narrow it down, but below are the top ten timelines produced by my students this semester.  Enjoy!

The Plague of Ancient Athens

The Battle of Gettysburg

The Start of the French Revolution

The Atomic Bombing of Hiroshima & Nagasaki

The Winter War

The Punic Wars: How Rome Conquered the Mediterranean

Prostitution in 18th & 19th-century France

The Spanish Flu

Eisenhower’s National Interstate and Defense Highway

Jack the Ripper: A Social Construct

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My “Master List” of Digital Humanities Centers/Projects/Initiatives (US only)

In an attempt to answer a question frequently asked on Twitter: “What universities have graduate programs in the digital humanities?” I offer up this latest post.  As of now, there is no “master list” of universities offering digital humanities courses at either the undergraduate or graduate level, provoking me to produce my own list of such programs.  However, as much as I believe my initial attempt to answer this question is a step in the right direction, it heavily relies upon a certain assumption.  My undoubtedly incomplete list found below is composed of DH centers, projects, and initiatives at a number of universities in the United States.  Considering that these universities have devoted substantial financial and intellectual resources to the study of the digital humanities, I assume that they also are offering courses on the subject as part of their regular curriculum.  Certainly @DHcenterNet’s list of digital humanities centers is a good place to start, but at the time of this post, the following serves as a more comprehensive list (please feel free to email me at r.jordan@colostate.edu to add additional universities to this list or to correct any of the information found below):

Alabama Digital Humanities Center at the University of Alabama

Baker-Nord Center for the Humanities at Case Western Reserve University

CATH: Center for Applied Technologies in the Humanities at Virginia Tech University

CDH: Center for Digital Humanities at the University of South Carolina

CDRH: Center for Digital Research in the Humanities at the University of Nebraska-Lincoln

Center for Digital Humanities and Culture at the Indiana University of Pennsylvania

Center for Digital Humanities at Brock University

Center for Digital Scholarship at Brown University

Center for Scholarly Communication & Digital Curation at Northwestern University

Centre for Oral History and Digital Storytelling at Concordia University

CHNM: Center for History and New Media at George Mason University

CMS: Comparative Media Studies at Massachusetts Institute of Technology

CPHDH: Center for Public History + Digital Humanities at Cleveland State University

CTSDH: Center for Textual Studies and Digital Humanities at Loyola University

CUNY Digital Humanities Initiative (all 24 CUNY campuses)

DHC: Digital Humanities Center at Columbia University

DHI: Digital Humanities Initiative at Hamilton College

Digital History Lab at California State University-San Marcos

Digital History Lab at Harvard University

Digital History Lab at Princeton University

Digital History Lab at the University of Massachusetts-Amherst

Digital Humanities 2.0 Collaborative at the University of Minnesota

Digital Humanities Initiative at Hamilton College

Digital Innovation Lab at the University of North Carolina

Digital Scholarship Commons at Emory University

Digital Scholarship Lab at the University of Richmond

Digital Studio for Public Humanities at the University of Iowa

DSC: Digital Scholarship Center at the University of Oregon

HASTAC: Humanities, Arts, Science, and Technology Advanced Collaboratory at Duke University

Humanities Research Center at Rice University

Humanities Technology and Research Support Center at Brigham Young University

I-CHASS: Institute for Computing in the Humanities, Arts, and Social Science at the University of Illinois

IDAH: Institute for Digital Research in the Humanities at the University of Kansas

IDHMC: Initiative for Digital Humanities, Media, and Culture at Texas A&M University

Institute for Advanced Technology in the Humanities at the University of Virginia

Interdisciplinary Humanities Research Center, University of Delaware

IRIS: Interdisciplinary Research and Informatics Scholarship Center at Southern Illinois University

MATRIX: Center for Humane, Arts, Letters, and Sciences Online at Michigan State University

MITH: Maryland Institute for Technology in the Humanities at the University of Maryland

Research in Computing for the Humanities at the University of Kentucky

SJCDH: South Jersey Center for Digital Humanities at Stockton College

Spatial History Project at Stanford University

Virginia Center for Digital History at the University of Virginia

Wired Humanities Project at the University of Oregon

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Public Market Construction in Mexico City, 1953-1964

The next step in my mapmaking project on Mexico City during Uruchurtu’s tenure as regent from 1952-1966 was the addition a new data set focused on the construction of new public markets not only within the confines of the Federal District, but within the greater Mexico City metropolitan area as well.  Before examining the processes by which I created this latest layer of data, a bit of historical background should be helpful.  From 1953-1966, Uruchurtu and the DDF were responsible for the construction of 172 new markets containing over 52,000 individual vendor stalls at an estimated cost of more than half a billion pesos.  Precise numbers for construction, renovation, and maintenance costs are very difficult to obtain from existing archival sources.  However, DDF records do show that from 1953-1958, the city spent 350 million pesos renovating existing markets or constructing new ones, representing almost 8.5 percent of the total expenditures by the DDF during this period.  The financial gains by the modernization of commerce in these new markets were insignificant, and such massive expenditures for the city treasury instead served as state propaganda and a guarantee of support from a new political interest group composed of comerciantes en pequeño (petty merchants).

This newly formed economic and political covenant with the Frente Unico de Locatarios y Comerciantes en Pequeño del D.F. would help to reverse the PRI’s political fortunes in Mexico City, helping to boost support for the ruling party among the working classes.  The openings of major markets such as La Merced, Jamaica, and Tepito were highly touted political events showcasing the commitment of the Revolution to bringing about economic equality for all.  In October 1957, the opening of a massive market containing 4,488 vendor stalls in the barrio of Tepito was attended by thousands of vendors, members of Congress, senior ministers, Uruchurtu and department chiefs within the DDF, and even President Adolfo Ruiz Cortines, reportedly the first Mexican president to ever step foot, let alone hold a major political event, in this neighborhood notorious for its poverty and street crime.

However, beyond the political gains which resulted from the construction of new, modern marketplaces, Uruchurtu sought to eliminate the disease, crime, and immorality which city officials associated with the “market days” or tianguis which had been a part of Mexico City’s economic and social traditions since the time of the Aztecs. These chaotic, unregulated markets were portrayed as being rife with pickpockets, dealt in black market goods, sickened residents through the sale of spoiled food, and corrupted the morality of the populace through the sale of cheap alcoholic beverages.  The commercial activity created by these marketplaces spilled out of plazas into the surrounding streets of the city.  Pedestrians and large trucks continually flowed past sidewalks filled with vendors’ stalls, slowing traffic to a crawl.

This “cork” on the flow of buses, sanitation crews, and general commerce reportedly affected more than 530,000 square meters of the urban landscape, and according to the DDF, was analogous to an “ever-growing cancer” on the city.  The destruction of these old markets and the containment of petty merchants within new, modern market buildings was a priority for the well-being of the city and its residents. Clean, modern markets complete with electric lighting, refrigeration, ventilation, an open, spacious design, childcare for vendors, and police surveillance could help to sanitize and decongest the city streets while at the same time improve the physical health of urban residents by providing them with fresh, healthy food and a safe, moral environment in which to shop for the basic necessities of life.

My data set on the period from 1953-1964 contains information on 129 public markets within the metropolitan area, for which I included the names, the number of stalls, and the latitude/longitude coordinates of each market.  As with the information on public lighting, this data came directly from the DDF’s own records at the Archivo Historico del Distrito Federal (AHDF) in Mexico City which I compiled during my dissertation research in the fall of 2011.  However, in my attempts to locate and verify the address information provided by the DDF, a fair amount of detective work was required.  The DDF data only provided the cross streets for each market’s address, a method which works fine for an address listing like Wagner y Mozart due to the unique street names.  However, the ease of geographically locating a market can be dramatically different with a listing like Constitucion y Jalisco, for which there might be four or five streets named Constitucion as well as Jalisco located throughout the city.

Additionally, in several cases, the address listing provided by the DDF (and sometimes the geographic marker provided by Google Maps, if there was one) was incorrect by entire city blocks.  This led me to walk the city streets using Street View in Google Maps, doing some detective work until I located the market around a corner or down the street several blocks.  This ability to virtually explore the city via Google was invaluable in making my map as accurate as possible and it really is a technological marvel that I can track down a public market in Mexico City from my computer at home here in Fort Collins.  What would normally take a physical visit to the city and possibly asking locals for directions now can be done in minutes on a computer thousands of miles away.  But I gush too much about my appreciation of all things Google.

As opposed to the previous layer of data on public lighting which was composed of both linear and polygon overlays onto Google Earth, I created three separate maps each capable of representing the data in a unique way.   For the first map, rendered on Google Earth, I imported my data set created in Excel into Google Fusion Tables, which then allowed me to create a .kml file which can be downloaded here.  A simple upload of the .kml file to Google Earth, and the new layer was added on top of the existing layer on public lighting.  This simple layer of pushpins is not very visually telling in itself, but the great thing about Google Earth is the ability for users to attach photos, videos, and links to other sites to each marked location on the map.

For La Merced, one of the more famous and grandiose markets in Mexico City from this time period, I attached an image of the market’s interior just prior to its opening in the fall of 1957.  Hypothetically, a group of users could collaboratively attach media and links to further information on any marked location on this map, creating an interactive, historical atlas of the city which visitors could explore location by location or via tours along preselected routes.  This interactive capacity is a big selling point for Google Earth as a means of conveying a variety of information on historical locations and its ease of use makes it possible for just about anyone to create a map quickly.

New Markets 1952-1964_google earth view

For the second map, I made the map pictured below using Tableau Public.  As I can’t embed html directly into this blog, please click here to explore the interactive version of this map.  For this visualization, I’ve linked the number of stalls attribute directly to the size of the bubble, moving beyond the simple pushpin display found on Google Maps/Earth.  This allows the viewer to see the relative size of each market based on vendor capacity and thus get a sense of market concentration in various parts of the city.

New Markets 1952-1964_tableau view

Lastly, to further analyze market concentration in various parts of the city, I used CartoDB to generate this map.  Again, please do click the link to see the interactive version.  This intensity map was created on my favorite basemap template, GMaps Dark (which I dearly wish other map programs had available), and uses three thermal rings surrounding each market location to emphasize the physical concentration of markets in various parts of the city.  It’s not quite as striking as a true choropleth map, but I just don’t have the data sets to do something like that for Mexico City.

New Markets 1952-1964_cartodb view

The process of creating these three maps has been an incredible learning experience for me both technically and as a scholar, and I hope the information conveyed helps to further illuminate this period of the city’s history.  My next layer of mapped data will likely be on new school construction, but first I plan to take a small break from maps to create my first network graph on Gephi.  Stay tuned for that graph in the very near future and thanks to everyone for the support, advice, and encouragement during this series of projects.

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Street Lamp Construction in Mexico City, 1952-1964

Image

For my initial mapmaking projects on Mexico City during Uruchurtu’s tenure as regent, I plan to focus on the construction of new public works throughout the growing metropolis.   As an aside, in my descriptions of this project as well as in future projects, will I use the terms “Mexico City” and the “Federal District” interchangeably, as both terms are commonly used to describe the geographic territory composed of the actual capital and its twelve surrounding delegations (administrative divisions).  The greater metropolitan area composed of numerous municipalities adjacent to the Federal District remained outside the domain of city leaders and was administered by corresponding state governments.  This first project will focus on the construction of new street lamps for the city, part of Uruchurtu’s plan to modernize and moralize the urban landscape.

During Uruchurtu’s first two terms as regent from 1952-1964, over 81,000 mercury lamps and over 35,000 incandescent lamps were installed throughout the metropolis, actions which purportedly turned Mexico City into “one of the best illuminated cities in the world.”  The geographic placement of these two basic types of lamps revealed the dual function which illumination could serve for the production of power within the spaces of the city.  In the wealthier colonias near the city center, DDF engineers installed 250 watt, mercury “colonial-style lanterns” which sought to “add a touch of bygone elegance, suitable to this part of the city which is a product of Mexico’s illustrious past.”  Uruchurtu and the DDF used the installation of such softly lit, ornate street lamps to reveal the beauty of this sector of the city, the tree lined sidewalks and colonial architecture of these older neighborhoods symbolic of an idealized cultural past.  Near the Centro Histórico, structures inscribed with cultural and nationalistic meanings such as the Catedral Metropolitana, the Palacio Nacional, and the Plaza de la Constitución were especially well illuminated.  These ornately illuminated religious and civic temples were capable of inspiring intense loyalty to the imagined community of la patria and served as powerful political instruments for the ruling party.

In contrast, for the colonias proletarias, the DDF installed extremely tall, 400 watt incandescent lamps which cast a wide arc of intensely bright light.  These modern, industrial looking street lamps were not designed to illuminate the beauty of the neighborhoods they were installed in.  Instead, they were intended to penetrate the dark spaces within working class neighborhoods, areas which were considered a breeding ground for immorality.  Within the rhetoric of urban planners, the electrification of these “modest zones” of the city went hand in hand with modernization, the safety and security they provided a “necessary requirement for any modern city.”  In early 1955, Uruchurtu ordered the Department of Public Works to cooperate with the DDF police in identifying gaps in the illumination of the colonias proletarias, with the regent’s focus primarily on the security aspect of lighting for the city.  The electrical illumination of these neighborhoods increased the visibility of residents to police patrols, thus discouraging the potential criminal activities of residents through an expansion of the state’s surveillant gaze.

The map displays major roadways and neighborhoods with mercury lamps in blue and the incandescent lamps in red.  To create this map, I compiled data from the public works archives of the Department of the Federal District (DDF) which provided street names and the types of lights, but not the exact total of lights attributed to each street.  The DDF data provided the total number of street lights constructed during this time period, but no data from year to year or month to month.  However, as much as this mapmaking project is incomplete in some respects, it is a starting point for further investigation and just one of many layers I hope to overlay on top of the city’s landscape in order to partially recreate Mexico City during this formative time period.  To view a more interactive version of this map (something which I highly recommend), you can directly download the .kml file to be opened with Google Earth here.  Stay tuned over the next week or two for another project on market construction.

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Mapmaking tools, my experience thus far

I’ve been spending a lot of time lately tinkering with potential mapmaking tools, looking at existing projects, and getting frustrated with my lack of knowledge on the developer/GIS side of things.  Modest Maps, Polymaps, and R can produce some excellent results, but they all require a basic understanding of programming in order to use them properly, a skill which I simply don’t have time to learn during the remainder of the summer.  ArcGIS on the other hand, the industry standard for professional cartographers, doesn’t require any programming knowledge, but its interface is incredibly complex and requires a great deal of training to understand.  Therefore, I’m going to stick with using some simple mapmaking tools for my first few cartography projects.

There are a number of intuitive mapmaking programs worth mentioning which are capable of quickly producing high quality results, so picking the easiest/best one can be difficult. Tableau, Many Eyes, GeoCommons, Indiemapper, CartoDB, and TileMill can all be used to build maps by uploading layers from a wide variety of data sources.  However, the simplicity of use and the customization options vary greatly among these programs.  Tableau is one of the more versatile and highly customizable tools, but it is extraordinarily expensive.  The personal edition and professional edition cost $999 and $1,999, respectively, at the time of this post.  However, there is a “public edition” of Tableau available for free, but just like Many Eyes, users are required to upload their work and cannot keep it private/unlisted.  GeoCommons, Indiemapper, CartoDB, TileMill, and Many Eyes are all free, but each mapmaking tool has its own set of strengths and weaknesses in visualizing certain kinds of data sets.  I’d recommend giving many of these sites a quick glance to see which program works best for your particular project, the right program being largely dependent on the complexity of the data set you are trying to visualize.

For now, Google’s toolset should work just fine to get me started.  Google just recently granted access to Google Maps Engine Lite, which allows you to create clickable layers (a much needed feature unavailable in Google Maps), but limits the size of the data sets to 100 rows.  Unfortunately, nearly all the projects I have in mind are much, much larger than 100 rows.  Therefore, to visualize the street lighting data, I plan on exporting my data from Google Maps into Google Earth as a .kml file, a task which isn’t as simple as a click of a button, but not hard to learn how to do.  From Google Maps, just click on the create a link button, which gives you a copy/pastable url for your map.  Paste that url into an empty address bar and type (without the quotation marks) “&output=kml” at the end of your url.  Hit enter and that should create a downloadable .kml file which you can then open with Google Earth.  So far, my data looks great superimposed over Google’s 2013 map of Mexico City, giving the viewer a good sense of the rapid growth of the city over the last 50+ years.  I should be able to finally publish the data in the very near future, so stay tuned.

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