The tun (, , ) is an English unit of liquid volume (not weight), used for measuring wine, oil or honey. Typically a large vat or vessel, most often holding 252 wine gallons, but occasionally other sizes (e.g. 256, 240 and 208 gallons) were also used.
History
Originally, the tun was defined as 256 wine gallons; this is the basis for the name of the quarter of 64 corn gallons. At some time before the 15th century, it was reduced to 252 wine gallons, so as to be evenly divisible by other small integers, including seven.
In one Early Modern English example from 1507, a tun is defined as 240 gallons.
With the adoption of the Queen Anne wine gallon of 231 cubic inches in 1706, the tun approximated the volume of a cylinder with both diameter and height of 42 inches. These were adopted as the standard U.S. liquid gallon and tun.
When the imperial system was introduced in 1824, the tun was redefined in the UK and its colonies as 210 imperial gallons. The imperial tun remained evenly divisible by small integers. There was also little change in the actual value of the tun.
Standard tuns of wine came to serve as a measure of a ship's capacity.
{|class=wikitable
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|rowspan=9|
!colspan=7|comparisons
|rowspan=9|
!historically
|rowspan=9|
!colspan=2|imperial definitions
|rowspan=9|
!colspan=2|US definitions
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!measure
!tuns!!butts!!puncheons!!hogsheads!!tierces!!barrels!!rundlets
!litres
!gallons
!litres
!gallons
!litres
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!tun
|align=center|1
|align=center|
|align=center|
|align=center|
|align=center|
|align=center|
|align=center|
|align=center|950–960
|align=center|210||align=center |954.6789
|align=center|252||align=center|953.923769568
|-
!butt
|align=center|2
|align=center|1
|align=center|
|align=center|
|align=center|
|align=center|
|align=center|
|align=center|475–480
|align=center|105||align=center|477.33945
|align=center|126||align=center|476.961884784
|-
!puncheon
|align=center|3
|align=center|
|align=center|1
|align=center|
|align=center|
|align=center|
|align=center|
|align=center|316–320
|align=center|70||align=center| 318.2263
|align=center|84||align=center|317.974589856
|-
!hogshead
|align=center|4
|align=center|2
|align=center|
|align=center|1
|align=center|
|align=center|
|align=center|
|align=center|237–240
|align=center|||align=center|238.669725
|align=center|63||align=center|238.480942392
|-
!tierce
|align=center|6
|align=center|3
|align=center|2
|align=center|
|align=center|1
|align=center|
|align=center|
|align=center|158–160
|align=center|35||align=center|159.11315
|align=center|42||align=center|158.987294928
|-
!barrel
|align=center|8
|align=center|4
|align=center|
|align=center|2
|align=center|
|align=center|1
|align=center|
|align=center|118–120
|align=center|||align=center| 119.3348625
|align=center| ||align=center|119.240471196
|-
!rundlet
|align=center|14
|align=center|7
|align=center|
|align=center|
|align=center|
|align=center|
|align=center|1
|align=center|68–69
|align=center|15||align=center|68.19135
|align=center|18||align=center|68.137412112
|}
Definitions
In the US customary system, the tun (symbol: US tu) is defined as 252 US fluid gallons, or exactly .
|-
|||≈||align=right| || cubic inches
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|||≈||align=right| || cubic feet
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|||≈||align=right| || cubic yards
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|||≈||align=right| || US gallons
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|||≈||align=right| || US liquid quarts
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|||≈||align=right| || US liquid pints
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|||≈||align=right| || US dry quarts
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|||≈||align=right| || US dry pints
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|
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|colspan=4|Conversions of the US tun are as follows.
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|1 US tun ||≡ ||align=right| 252 || US gallons
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|||≡||align=right| || cubic inches
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|||≡||align=right| || cubic feet
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|||≡||align=right| || cubic yards
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|||≈||align=right| || imperial gallons
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|||≈||align=right| || imperial quarts
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|||≈||align=right| || imperial pints
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|||≡||align=right| || US dry quarts
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|||≡||align=right| || US dry pints
|}
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Explanatory notes
See also
- Tonelada