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Be a Wise Consumer of “Fun” Posts, too!

January 1, 2017 5 comments

Versions of the following story have made their way around the internet recently:

The passenger steamer SS Warrimoo was quietly knifing its way through the waters of the mid-Pacific on its way from Vancouver to Australia. The navigator had just finished working out a star fix & brought the master, Captain John Phillips, the result. The Warrimoo’s position was LAT 0º 31′ N and LON 179 30′  W.  The date was 31 December 1899.

“Know what this means?” First Mate Payton broke in, “We’re only a few miles from the intersection of the Equator and the International Date Line”.  Captain Phillips was prankish enough to take full advantage of the opportunity for achieving the navigational freak of a lifetime.  He called his navigators to the bridge to check & double check the ships position.  He changed course slightly so as to bear directly on his mark.  Then he adjusted the engine speed. The calm weather & clear night worked in his favor. 

At midnight the SS Warrimoo lay on the Equator at exactly the point where it crossed the International Date Line! The consequences of this bizarre position were many:  The forward part (bow) of the ship was in the Southern Hemisphere & the middle of summer. The rear (stern) was in the Northern Hemisphere & in the middle of winter.  The date in the aft part of the ship was 31 December 1899.  Forward it was 1 January 1900.  This ship was therefore not only in two different days, two different months, two different years, two different seasons, but in two different centuries – all at the same time.

I have successfully used many types of geographic puzzles with students and with the general public over the years, and I enjoy this story a great deal.  But in keeping with our reminders on this blog and in our book to “be critical of the data,” reflections on the incorrect or absent aspects to this story can be instructive as well as heighten interest. The SS Warrimoo was indeed an actual ship that was built by Swan & Hunter Ltd in Newcastle Upon Tyne, UK, in 1892, and was sunk after a collision with a French destroyer during World War I in 1918.  Whether it was sailing in the Pacific in 1899, I do not know.

The version of this story on CruisersForum states that it is “mostly true.”  What lends itself to scrutiny?  Let us investigate a few of the geographic aspects in the story.

First, the statement, “working out a star fix” leaves out the fact that chronometers were used to work out the longitude, rather than a sextant.  (And I highly recommend reading the book Longitude by Dava Sobel).  Second, the International Date Line (IDL) as we know it today was not in place back in 1899.  The nautical date line, not the same as the IDL, is a de jure construction determined by international agreement. It is the result of the 1917 Anglo-French Conference on Time-keeping at Sea, which recommended that all ships, both military and civilian, adopt hourly standard time zones on the high seas. The United States adopted its recommendation for U.S. military and merchant marine ships in 1920 (Wikipedia).

Third, the distance from LAT 0º 31′ N and LON 179 30′ W to LAT 0º 0′ N and LON 180′ W is about 42 nautical miles, and the ship could have traveled at a speed of no more than 20 knots (23 mph).  Therefore, conceivably, the ship could have reached the 0/180 point in a few hours, but whether it could have maneuvered in such a way to get the bow and stern in different hemispheres is unlikely, given the accuracy of measurement devices at the time.  Sextants have an error of as at least 2 kilometers in latitude, and chronographs about 30 kilometers in longitude. Or, they could already have reached the desired point earlier in the day and not have known it.  An interesting geographic fact is that, going straight East or West on the Equator along a straight line, it is possible to cross the dateline three times (see map below).

Our modern digital world is full of fragments that are interesting if not completely accurate, but I think as GIS professionals and educators, it is worth applying “be critical of the data” principles even to this type of information.  The story is still interesting as a hypothetical “what could have happened” and provides great teachable moments even if the actual event never occurred.

international_date_line

The International Date Line (CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=147175).