Steelyard
2 of the 7 encyclopedias on this shelf carry an entry for Steelyard. Both are reproduced below, so you can see where they agree and where they differ.
Aiton's Encyclopedia (1910)
a place in London in which at an early date the merchants of the Hanseatic League maintained immense warehouses for the sale of their goods. The topic is of interest chiefly for the caution it lends not to be hasty in concluding that words are related because they are spelled alike. The first syllable of the name is a corruption of stael, meaning a leather tag or seal affixed to a bolt of cloth as a certificate of proper dyeing. In 1597 the London merchants, desiring the business for themselves, secured the passage of an act driving the Hanse merchants from the city. Staelyard became corrupted to Steelyard, and still later popular tradition had it that the place was called Steelyard because it was formerly a yard for the sale of steel and iron. Then by a curious, and, we may say, an ignorant, association of terms, for the word is of a wholly different origin, the common steelyard or bar used as a balance in weighing was said to derive its name from its early employment by the Hanse merchants in weighing out steel to their customers. This false history of the word "steelyard" was current for a century.
Collier's New Encyclopedia (1921)
a balance or weighing machine consisting of a lever with unequal arms. It is of two kinds. The common steelyard, or Roman balance, is formed by suspending the article to be weighed from the end of the shorter arm, or placing it in a scale depending therefrom and sliding a determinate weight along the longer one till an equilibrium is obtained. The longer arm is so graduated that the figure opposite to which the weight rests indicates the weight of the article at the extremity of the shorter arm. The second form is the Danish balance, which differs from the Roman in having the counterpoise fixed at one end and the fulcrum slid along the graduated beam.