Cyathi to US Gallons (cyathus to gal)
1 cyathus equals 0.01201615933 US gallons (rounded).
How to convert cyathi to US gallons
To convert cyathi to US gallons, multiply the number of cyathi by 0.01201615933. The factor is rounded to 10 significant digits. To go the other way, multiply US gallons by 83.2212667 (rounded).
US gallons = cyathi × 0.01201615933
Example: 10 cyathi = 0.1201615933 US gallons.
Pints, quarts, gallons and fluid ounces differ between the US and the UK. Units are labeled 'US' or 'imperial' to avoid confusion.
Approximate value. Standards for the cyathus varied by place and period, so this converter uses the most commonly cited value. Treat results as estimates, not exact figures.
About these units
Cyathus (cyathus)
One twelfth of a sextarius, about 45 mL. A small Roman ladle or wine cup.
Greek kyathos, a cup or ladle, lies behind the Latin cyathus. In Roman use it was the small dipper for taking wine from a mixing bowl and filling drinking cups, so it served as the basic unit for serving rather than for trade. Wikipedia lists it as 1/72 of a congius, or 45 mL, the figure used here.
It appears in both the liquid and the dry tables, where it is one twelfth of a sextarius, so twelve cyathi filled the sextarius and 576 filled an amphora quadrantal. The unit therefore inherits the uncertainty of the sextarius, which scholars estimate at 500 to 580 mL from surviving vessels, putting a cyathus somewhere between about 42 and 48 mL. In modern terms it is a little over one and a half US fluid ounces, about the size of a shot glass or a generous tablespoon and a half.
1 cyathus = 0.04548611111 liters (approximately).
Sources: Wikipedia: Ancient Roman units of measurement; Wikipedia: Cyathus (genus), on the Greek kyathos
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 cyathi (reverse)
- Cyathi to liters
- Cyathi to milliliters
- Cyathi to US cups
- Cyathi 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.