US Pecks (pk) to Glas (glas) conversion

What is the US Peck?

The US peck is a United States customary unit of dry volume, equal to a quarter of a bushel, used for measuring fruit, vegetables, and grain. It sits between the dry gallon and the bushel in the dry-measure system.

Definition

The US peck is defined as one quarter of a US bushel, or 8 US dry quarts, equal to exactly 537.605 cubic inches.

$$1\ \text{pk} = 8.80977\ \text{L}$$

With the bushel fixed at 2150.42 in³, a peck equals 2150.42 ÷ 4 = 537.605 in³ = 8809.77 cm³, a value the NIST Guide to the SI lists as 8.809 768 × 10⁻³ m³. The US peck is about 3% smaller than the imperial peck (9.09218 L).

Origin and History

The peck is an old English dry measure, attested since the 14th century and long used for grain and produce. Its US form is tied to the Winchester bushel retained from colonial England, while the imperial peck follows Britain's 1824 reform.

Law and Notable Facts

The peck endures in the tongue-twister "Peter Piper picked a peck of pickled peppers" and in US orchard sales, where apples are still sold by the peck and half-peck. It remains a legal customary unit defined via the international inch.

Real-World Examples and Conversions

• A peck of apples weighs roughly 10–12 lb and fills about 8.81 liters.
• 1 US peck = 8 US dry quarts = 16 US dry pints = 8.80977 L.
• 4 US pecks make 1 US bushel; 1 liter ≈ 0.11351 US peck.

What is Glas?

Glas is a Swedish unit of volume used in cooking and baking. The word "glas" is Swedish for "glass," reflecting its origin as a measure based on the contents of a drinking glass. In modern Swedish recipes it is a standardized measure.

Definition of Glas

In the standardized Swedish system of kitchen measures (matmått), one glas is defined as 2 deciliters, which is equal to 200 millilitres.

$$1 \text{ glas} = 2 \text{ dL} = 200 \text{ mL} = 0.2 \text{ L}$$

Like the other Swedish cooking measures (kryddmått, tesked, matsked, and kaffekopp), the glas follows the metric system, so conversions to litres and millilitres are exact.

Relationship to Other Units

The glas fits neatly into the family of Swedish volume measures and the wider metric system:

• 1 glas = 200 mL = 20 centilitres
• 1 glas = 2 deciliter (dL)
• 1 glas ≈ 6.76 US fluid ounces
• 1 glas ≈ 7.04 Imperial fluid ounces
• 1 glas ≈ 0.85 US cups

Because 1 kaffekopp (coffee cup) is 1.5 dL, a glas (2 dL) is slightly larger than a kaffekopp.

Historical Context

The glas belongs to the set of household measures that Swedish cooks have long used in place of scales. As Sweden adopted the metric system in the late 19th century, these traditional kitchen measures were standardized to round metric values, giving the glas its modern value of 2 dL. There is no single law or historical figure directly associated with it; rather, it reflects the gradual standardization of everyday cooking measurements.

Real-World Examples

Glas measurements appear frequently in Swedish and Scandinavian recipes:

• Baking: A cake recipe might call for 3 glas of flour.
• Cooking: A sauce or soup might need 1 glas of cream or stock.
• Drinks: Punch and cordial recipes are often measured in glas.

Converting Glas

Because the glas is defined in exact metric terms, conversion is straightforward. To convert a volume in glas to litres:

$$\text{Volume in Liters} = \text{Volume in Glas} \times 0.2$$

For example, 4 glas equals $4 \times 0.2 = 0.8$ litres (800 mL).