Units of Measure

Currently I'm reading a translation of Arturo Pérez-Reverte's book The Siege. He's the author of the very good Alatriste series that I mentioned in a previous post. This isn't a book review so that is all by way of preamble. In beginning of The Siege there is a List of Currency, Weights, and Measurements which includes the toise, "an Old French measurement equivalent to about 6 feet." The term sounded vaguely familiar which piqued my interest. So I looked it up and learned that, the toise is about six pieds (a pied in the old English measure (the kind we Americans still use) or about 2 meters. 

Which is perfect for use in a game since it is (a) authentic and (b) close to something already familiar to the players, e.g. feet for the USA and meters for the other folks.

Here's a table of ancien France linear measures from the article, Units of measurement in France before the French Revolution.

Unit	Relative value	SI value	Imperial value	Notes
point	1/123	~0.188 mm	~7.401 thou	This unit is usually called the Truchet point in English.
ligne	1/122	~2.256 mm	~88.81 thou	This corresponds to the line, a traditional English unit.
pouce	1/12	~27.07 mm	~1.066 in	This corresponds to the inch, a traditional English unit.
pied du roi	1	~32.48 cm	~1.066 ft	Commonly abbreviated to 'Pied', this corresponds to the foot, a traditional English unit. Known in English as the Paris foot (properly a separate, shorter unit), the royal foot, or French foot.
toise	6	~1.949 m	~6.394 ft, or ~2.131 yd	This corresponds to the fathom, a traditional English unit. Unlike the fathom, it was used in both land and sea contexts.
(league) lieue ancienne		~3.248 km	~2.018 mi	This is an old French league, defined as 10,000 (a myriad) feet. It was the official league in parts of France until 1674.

So I can use authentic measures: pouce, pied, toise, and lieue or switch to their English or metric equivalents, e.g. inches, feet, and miles.

Now I just need to remember that a French league is only 2 miles.