The Daily Parker

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Analysis of Shanks' atlases against the tzinfo database

To better understand the facts behind Astrolabe’s stupid trolling quixotic lawsuit against the guys who coordinated the worldwide time-zone database (tzinfo), I bought copies of the Shanks Amercian and International atlases that Astrolabe claims to own. (I went through the secondary market, so I didn’t actually give Astrolabe any money.)

First, an update. According to Thomas Eubanks of the IETF, the Electronic Frontier Foundation has taken over Arthur Olson’s legal defense. Mazel tov. I expect to see a response to the complaint against him in a few weeks that includes a motion to dismiss which, I think, may be granted. (I’m thinking about drafting a response myself, just to exercise my legal muscles properly. Watch this space.)

Now to the main post. The Shanks books, rather than containing maps, contain pages and pages of tabular data showing three things:

  1. Names of first- and second-order administrative districts (e.g., states and counties);
  2. Latitudes and longitudes of cities and other named places within countries or states;
  3. Lists of the dates and times of time-zone changes for those named places.

The atlases dump this data to paper using a monospace typeface at 6-point size in what can be nothing other than 1990s-era printouts to some kind of publishing compositing software. This offers a clue to the “original works” claim that Astrolabe makes about the products.

Shanks certainly put a lot of work into these books, especially considering he first published them in 1978 and 1985. He must have spent hundreds of hours looking up and entering data on the thousands of locations in the tables.

For example, the American Atlas contains rows upon rows of data like this:

Chicago 16      1 41N51'00 87W39'00 5:50:36
Chicago Heights 16
                1 41N30'22 87W38'08 5:50:33
Chicago Lawn 16 1 41N47    87W43    5:50:52

I imagine Shanks looked up this data in reference books, then entered it into a home-grown flat-field database through a Vax terminal or on his Apple ][+. I hope he at least let the computer calculate the last column (the location’s offset from GMT), since it’s derived directly from the location’s longitude (the next-to-last column).

I imagine this because, in the early 1990s, I did something similar to study climate data. (Do you know how long it takes to enter 30 years of daily climate data by hand? No? You’re lucky.)

Back to Astrolabe’s complaint. In Count 4, Astrolabe claims ownership of “certain copyright-protected computer software programs and information contained therein…known as the ‘ACS Atlas,’ consisting of both the ‘ACS International Atlas,’ and the ‘ACS American Atlas,’ in the form of computer software program(s) and/or data bases, and in the form of electronic output and future electronic media from said programs....’ ” I infer from the complaint that the software reproduces the books in computer-searchable form, or perhaps contains the raw data that Shanks himself used to produce the books.

I’ll defer my main argument for a moment to speculate further on what parts of the tzinfo database could have copied the Shanks database.

In the tzinfo database, one of the files ( contains latitudes and longitudes of locations in this form:

US	+415100-0873900	America/Chicago	Central Time
US	+375711-0864541	America/Indiana/Tell_City	Central Time - Indiana - Perry County
US	+411745-0863730	America/Indiana/Knox	Central Time - Indiana - Starke County

Nothing else in the tzinfo database comes as close to looking like data in the Shanks atlases. I don’t know where the tzinfo list came from, but I suspect it came from public sources like the Census Bureau.

The other possible copying comes from the lists of dates Shanks put together that look like this:

IL # 1
Before 11/18/1883  LMT
11/18/1883  12:00  CST
 3/31/1918  02:00  CWT
10/27/1918  02:00  CST

Here’s how the tzinfo database shows the same information:

Rule	Chicago	1920	only	-	Jun	13	2:00	1:00	D
Rule	Chicago	1920	1921	-	Oct	lastSun	2:00	0	S
Rule	Chicago	1921	only	-	Mar	lastSun	2:00	1:00	D
Rule	Chicago	1922	1966	-	Apr	lastSun	2:00	1:00	D
Rule	Chicago	1922	1954	-	Sep	lastSun	2:00	0	S
Rule	Chicago	1955	1966	-	Oct	lastSun	2:00	0	S
Zone America/Chicago	-5:50:36 -	LMT	1883 Nov 18 12:09:24
			-6:00	US	C%sT	1920
			-6:00	Chicago	C%sT	1936 Mar  1 2:00
			-5:00	-	EST	1936 Nov 15 2:00
			-6:00	Chicago	C%sT	1942
			-6:00	US	C%sT	1946
			-6:00	Chicago	C%sT	1967
			-6:00	US	C%sT

That hot mess establishes the specific rules Chicago used to change its clocks in the 1920s and 1950s where the rules differed from the general U.S. rules, then it sets out the dates and times that Chicago’s wall-clock rule sets changed from the beginning of standard time in 1883 through the last change in 1967. (The current rule set for Chicago are the “US” rules, defined elsewhere in the database.)

Shanks has a list, and the tzinfo database has the rules to create the list. Shanks also has an error that the tzinfo database corrects: the tzinfo database establishes that Chicago switched from local mean time (LMT) to standard time at 12:09:24, because Chicago is 9 minutes and 24 seconds ahead of the standard meridian for the time zone. Shanks puts the time at 12 noon, because his list shows the target time, not the trigger time, for the rule change.

Did the tzinfo project use Shanks to determine the rules for time changes? Yes, explicitly, though for highly-documented locations like Chicago the project participants cross-referenced Shanks with original sources, often correcting his errors. But "use" does not mean "copy;" I can use all the baseball statistics I want out of the newspaper without ever copying the newspaper. Data is not protected by copyright.

The tzinfo didn’t infringe on anyone’s copyright because Shanks created very little to protect. As I’ve previously explained, facts and data do not enjoy copyright protection in the United States. Only the expression of facts does. So if the tzinfo project had photocopied Shanks’ atlases, or republished the ACS software wholesale, then perhaps there would be an infringement. But I think I’ve shown a bit of why the tzinfo project hasn’t done anything actionable.

The Shanks atlases are like meticulously hand-copied illuminated codices from the 16th century, years after Gutenberg made his Bible and made hand-copying obsolete. I’m glad Shanks did the work; I’m sure he felt like he’d accomplished something huge. I really admire the work that went into it, while at the same time shaking my head at the wasted effort. Because since the late 1990s, all that data—latitudes, longitudes, place names—has been available for free from the Census Bureau and the CIA.[1] Before around 1998, you couldn’t just download the data through FTP for free; you had to write a letter to the appropriate agency and pay for it. But being U.S. government data, it was in the public domain, so once you’d paid for it, you could republish it in an easier-to-use form and recoup royalties.

In an era before the Census Bureau started dumping terabytes of data to the Internet, Shanks’ atlases would have been incredibly convenient sources of geographic and time-zone data. Today, they’re curiosities, monuments to exactly the kind of mental effort obviated by fast, cheap computers and the Internet.

Poor Shanks, all those data, thousands of rows of it, standing nakedly, and often erroneously, on page after page of tables in two massive volumes, apparently not knowing that he could have gotten it from the U.S. government—you have to admire that work ethic.

Astrolabe, for its part, has degenerated into exactly the kind of mental deficiency reviled by those of us who actually create software for a living. I eagerly await their much-deserved legal defeat in the next few months.

[1] Yes, the CIA publishes tons of free data, from their World Factbook to entire databases of geospatial information.

Edited at 20:58 UTC: Clarified the difference between "use" and "copying."

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