Tierces to US Gallons (tierce to gal)
1 tierce equals 42 US gallons exactly.
How to convert tierces to US gallons
To convert tierces to US gallons, multiply the number of tierces by 42. This factor is exact. To go the other way, multiply US gallons by 0.02380952381 (rounded).
US gallons = tierces × 42
Example: 10 tierces = 420 US gallons.
Pints, quarts, gallons and fluid ounces differ between the US and the UK. Units are labeled 'US' or 'imperial' to avoid confusion.
About these units
Tierce (tierce)
42 US gallons (159 L), a third of a tun. The size of a standard oil barrel.
Tierce is French for a third, and the cask earned the name as a third of a wine pipe, holding 42 wine gallons. Wikipedia credits a definition under Richard III with fixing the wine tierce at that size, and by around 1700 it was a standard shipping container for many goods in the English colonies, not only wine.
Its best known afterlife is in the oil fields. Pennsylvania producers, who started after the Drake well of 1859, first used whatever barrels they could find, including 40 and 45 gallon ones. Around 1866 they settled on the wine tierce, two gallons larger than a standard whisky barrel, and the 42 gallon figure was formally standardised by 1872 and adopted by federal agencies in 1882.
In US gallons the tierce is about 159 litres (158.99 L as used here), and the imperial equivalent of 35 gallons is nearly identical at 159.1 litres. That coincidence is why the unit lives on in the oil barrel, still quoted in petroleum markets even though no one ships crude in wooden casks of that size.
1 tierce = 158.9872949 liters (approximately).
Sources: Wikipedia: Barrel (unit); Wikipedia: Tun (unit)
US Gallon (gal)
Exactly 231 cubic inches or 3.785411784 liters (128 US fluid ounces). About 17% smaller than the imperial gallon.
The US gallon is a survivor of English wine trade. Around 1706, a statute in Queen Anne's reign fixed the wine gallon at exactly 231 cubic inches, settling confusion among the competing gallons for wine, ale and corn. British colonies in North America used that wine gallon, and in 1824 Britain replaced all its gallons with a new imperial one while the United States kept the old measure. It was adopted as the legal US standard in 1836 and is still defined as exactly 231 cubic inches, or 3.785411784 liters.
That makes the US gallon about 17 percent smaller than the imperial gallon, a difference that explains why American and British fuel-economy figures cannot be compared directly. Everyday uses are milk jugs, paint cans and gasoline pumps. One gallon divides evenly into four quarts, eight pints, sixteen cups and 128 fluid ounces. A gallon of water weighs a little over 8 pounds, an easy figure to remember when loading a car with water jugs.
1 US gallon = 3.785411784 liters (exactly).
Sources: Wikipedia: Gallon; NIST SP 811, Appendix B.8: conversion factors for volume
Related conversions
- US gallons to tierces (reverse)
- Tierces to liters
- Tierces to milliliters
- Tierces to US cups
- Tierces to US fluid ounces
- Liters to US gallons
- Milliliters to US gallons
- US cups to US gallons
- US fluid ounces to US gallons
- Cubic meters to US gallons
- Cubic centimeters to US gallons
- US quarts to US gallons
- US pints to US gallons
- US tablespoons to US gallons
- US teaspoons to US gallons
- Metric cups to US gallons
- Metric tablespoons to US gallons
See all volume units.