Note:  Do not rely on this information. It is very old.

Yard

Yard, an English measure of length containing 3 feet or 36 inches. The standard yard, which is carefully preserved together with its authorized copies, is a bar of metal 1 inch square, consisting of a composition of 16 ozs. copper, 2-1/2 ozs. tin, and 1 oz. zinc. In this bar are set two gold pins with dots marked upon them, and the distance between these dots at a temperature of 62 F constitutes the regulation yard.

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