corn gallon, Winchester gallon

Also called the corn gallon or the dry gallon. In England, 12th – 19th centuries, a unit of dry capacity often used for grain, = 1/8 bushel. The qualifier “Winchester” was not used in statutes before the 17th century, though it occurs much earlier in other contexts.

Originally the volume occupied by 8 Troy pounds of grains of wheat from the middle of the ear. The earliest sources do not say what sort of pounds were meant, but slightly later ones do specify Troy weight. Some sources and commentators suggest the corn gallon was the volume occupied by 8 Troy pounds of wine; however, that volume is much smaller than any known volumes of the corn gallon.

That the measure of a bushel contains VIII gallons of wheat and that every gallon contain VIII pounds of wheat of Troy weight and every pound contains 12 ounces of Troy weight… according to the old laws of this land.

Act 12 Henry VII c 5 (1496)
Statutes of the Realm, vol 2, pages 637-638.

Today's wheat is not necessarily the same as Elizabethan wheat; in fact, it is not the same. Fortunately, earlier students of the subject measured the bulk density of wheat for just this purpose, so we do have published pre-pesticide, pre-fertilizer, pre-plant breeder values. Taking one value from 1775 makes 8 Troy pounds of wheat 239.5 cubic inches.

The earliest prototype that survives is the corn gallon of Henry VII, made in 1497 and now in the Science Museum, London. Twentieth-century measurements show it has a capacity of 268.43 cubic inches.

R. D. Connor has proposed the following explanation for the difference between the statute and the prototype: it arose from the almost universal tendency of sellers to give a little extra, i.e., buyers wanted their grain heaped. The law, however, said that the legal bushel was stricken, that is, leveled. To make up for measuring by level bushels, sellers gave 9 level bushels for 8 of the usual heaped ones. There is documentary evidence of this practice dating back to the 14th century. The prototypes were made to reflect the actual practice in the marketplace, that is, the prototype bushel, on the assumption that it would be used stricken, held 9 gallons, not 8, and the prototype gallon held 1 1/8 gallons. One and one-eighth of 239.5 cubic inches is 269.4 cubic inches, very close to the actual size of the Henry VII's prototype gallon.

Two gallon standards survive from Elizabeth I's time, made in 1601. Twentieth-century measurements give capacities of 270.59 cubic inches and 268.97 inches. The larger seems to have been chosen as the primary standard. A measurement of this standard by the Carysfort committee of 1758-1760 gave a value of 271 cubic inches. In any case, a value of 272 or 272¼ cubic inches came to be accepted as the size of the corn gallon.

In 1698 the bushel was redefined and specifically named the Winchester bushel, reducing the Winchester gallon to 268.8 cubic inches, close to the value in Henry VII's time. Please see Winchester bushel for an account of the circumstances. Nonetheless, some use of the dry gallon with the old magnitude continued, even in the laws:

1805, 45 G. 3. and I[rish] A[ct] 35 G. 3. In several late Acts of Parliament 272¼ cubic inches are mentioned as the content of a Winchester gallon, making 2,178 in a bushel.ยน

With the introduction of imperial measure in 1824, the Winchester gallon was abolished along with the Winchester bushel.2

1. First Report of Commissioners appointed to consider the Subject of Weights and Measures. 7 July 1819.
Parliamentary Papers (HC 565).

Appendix B, page 10.

2. 5 George IV chap. 74.
Statutes at Large, vol 23, page 759.


R. D. Connor.
The Weights and Measures of England.
London: H.M.S.O. 1987.

See chapter 9.



Dry Measure is different both from the Wine and Ale Measure, being as it were a mean betwixt both, tho' not exactly so; which upon Examination I find to be in proportion to the aforesaid old Standard Wine Gallon, as Averdupois Weight is to Troy Weight; That is, as one Pound Troy is to one Pound Averdupois, so is the Cubick Inches contained in the old Wine Gallon: To the Cubick Inches contained in the Dry or Corn Gallon.

Viz. 12 : 14 12/20 :: 224 : 272½, which is very near to 272¼, the common received content of a Corn Gallon, altho' now it's otherwise settled by an Act of Parliament made in April 1697, the Words of that Act are these:

Every Round Bushel with a plain and even Bottom, being made Eighteen Inches and a half wide throughout, and Eight Inches Deep, should be esteem'd a Legal Winchester Bushel, according to the Standard in his Majesty's Exchequer.

Now a Vessel being thus made will contain 2150.42 Cubick Inches, consequently the Corn Gallon doth contain but 268 4/5 Cubical Inches.

Cub. Inches
268.8 = 1 Gallon
537.6 = 2 = 1 Peck
2150.4 = 8 = 4 = 1 Bushel
17203.2 = 64 = 32 = 8 = 1 Quarter

Note, 4 Bushels = a Comb. 10 Quarters = a Wey, and 12 Weys = a Last of Corn.

John Ward.
The Young Mathematician's Guide… Fourth Edition.
London: Printed for A. Betterworth … and F. Fayrham, 1724.
Pages 35 and 36.


Your Committee also observing, that in the Trial made of three Gallons in the Receipt of the Exchequer in 1688, viz., of Henry the 7th, and two of 1601, they are said to contain each 272 cubical Inches; and upon the Trial in the Exchequer in 1700, it was made appear, that there was a Standard Gallon in the Exchequer, which contained 282 cubical Inches; and those, who made the Trial in 1688, taking no Notice of a second Gallon Measure in Henry the 7th's Time, your Committee thought it necessary to have all the Gallons, and other Measures of Capacity, kept in the Receipt of the Exchequer, measured with the greatest Accuracy and Exactness; but finding from the Figures of those Vessels that it was impossible to gauge them with sufficient Certainty, they ordered an Apparatus to be made by one of the best Artists in London, Mr. Bird, under the Directions of Mr. Harris; and the Vessels in the Exchequer having been measured accordingly in the Presence of your Committee, they appeared to be as follows:

The Standard Bushel made use of at the time of Queen Elizabeth, dated 1601, Contains 2124 cubical Inches.

The Standard [corn] Gallon made use of, dated 1601, marked with an E. and Crown, Contains 271 cubical Inches.

The Standard [ale] Quart, dated 1601, Contains 70 cubical Inches.

The Standard Pint, dated 1602, Contains 34 8/10 cubical Inches.

The Standard Wine Gallon, dated 1707, Contains 231 2/10 cubical Inches.

Report from the Committee Appointed to Inquire into the Original Standards of Weights and Measures in this Kingdom, and to Consider the Laws relating thereto. [Carysfort Report, 1760]
Reports from Committees of the House of Commons (1737-65), Vol. II, page 433.

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