Canadian feet
by Gene_Nygaard on 12/08/04 at 10:03:54

You say
[shadow=red,left,300]Wednesday, September 8th, 2004
- Changed the Foot [pre-1959 Canada] length unit to the Foot [pre-1963 Canada] unit. Canada went with the British Weights and Measures Act of 1963.[/shadow]

As far as the English units go, the British Weights and Measures Act of 1963 has nothing to do with Canada.  In fact, Canada needed to take no action whatsoever to implement the 1959 agreement on common definitions among the national standards laboratories of the U.S., Canada, the U.K., South Africa, Australia, and New Zealand.  That's because the values adopted internationally are the ones which were already official in Canada, adopted in the [b]Canadian[/b] Weights and Measures Act of 1953.  Those definitions are:
[center]1 yard = 0.9144 metre
1 pound (avoirdupois) = 0.45359237 kg[/center]

Before 1953, the relationship between the English foot in Canada and the metre was likely a measured one, depending on an independently maintained standard for the yard.  I do not know what the best value for this measured quantity was.

However, there is a much bigger problem here.  No British Weights and Measures Act could have any effect on what you characterize as the "Foot (pre-1963 Canada" because that is not a British unit at all:

[shadow=red,left,300]1 foot [pre-1963 Canada] = 325 millimeter[/shadow]

This unit was never in use Canada-wide.  It was limited (at least primarily) to the province and earlier French colony of Quebec.  (Was Quebec ever independent?  I remember postage stamps from an independent Newfoundland.)

It was related to another unit you have:

[shadow=red,left,300]1 arpent [Canada] = 0.8448261 acre[/shadow]

This was the square of a length unit also called the arpent, equal to 30 [i]toises[/i] of 6 feet [i](pieds)[/i] each.  Your figure in acres corresponds in English feet to 36800.624916 ft².

length 191.83488972551369546138679105958 ft

1 pied = 1.0657493873639649747854821725532 ft

  = 324.840 mm

Note that you could also call this a "U.S. foot" in the same way as you call it a "Canada foot"; the same units were used for the original land surveys in Louisiana.

I do not know when this "foot" was dropped from Quebec surveys.  I suspect it was in the 19th century or early 20th century, long before 1953.  I think it was replaced by the English foot, not going directly into metres.  Check on this.

You do also have that length of arpents, with a conversion factor that does not exactly correspond to your area in arpents

[shadow=red,left,300]1 arpent [Canada] = 58.47 metre[/shadow]

For your French values, you use the conversion to modern English inches as primary (since that has fewer than 7 digits after the decimal point).
[shadow=red,left,300]1 pied de roi = 0.3248406 metre
1 pied de roi = 12.789 inch [international, U.S.][/shadow]

I'd suggest that 324.84 mm would be a better conversion for at least the French version (for Quebec, the 12.789 inches, in their pre-1953 Canadian definition, whatever that is, might be better).

I have my doubts that the Quebec French foot was ever redefined as exactly 325 mm, though I will concede that as a possibility.  Even if it was, that value would not likely have been applied to preexisting survey measurements.

Gene Nygaard

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