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Weighty matters of mass.
AN OLD RIDDLE ASKS WHAT WEIGHS MORE, a ton of feathers or a ton of bricks? Perhaps a slightly harder question would be: what weighs more, a tonne of feathers or a ton of bricks? An even harder question would be, what weighs more, a tonne of feathers or a long ton of bricks?
The riddles can only be answered by clarifying the various types of tons. Confusion begins because a ton can be a unit of mass as well as a unit of volume. The ton is derived from the tun, which describes the volume of a wine barrel of the largest size.
A tun is a barrel that is six times larger than the common barrel, originally 256 gallons but later reduced to 252 gallons in order to be evenly divisible by small integers. It is also approximately the equivalent volume of a cylinder 42 inches in both diameter and height. The mass of a tun of wine and its barrel is approximately equal to a long ton.
A...