How the Ancient Greeks Pioneered Units of Measurement

The ancient Greeks developed sophisticated units of measurement ranging from measuring length, distance, volume, and weight of solids and liquids.

Naturally, the units varied according to location and era, as they reformed in the process. Around 500 BC, Athens established an official weights and measures depository called the Tholos. Merchants were required to test their measuring devices against the official standards there.

Some measuring units were first introduced by the Egyptians and then adopted by the Greeks. Similarly, the Romans adopted measuring units that were introduced by the Greeks.

The Earliest Attested Unit of Measurement

The cubit was a commonly used unit of length invented by the Egyptians. It is the earliest attested unit of measurement from the Old Kingdom pyramids and was later used by the ancient Greeks and other civilizations.

The Egyptian hieroglyphic symbol for the cubit is a drawing of the forearm, indicating it is a measuring unit that derives from the human body. It was the distance from the peak of the elbow to the tip of the middle finger and was the basis of other units based on the human body. The digit was the width of a thumb, and a palm was the width of a hand.

In most ancient civilizations, four digits made a palm, and five palms made a cubit. Fractions of a cubit were also used. Wood and stone cubit standards dating from 2400 BC to the first century AD and the variation over a long period of these standards varied less than 5 percent.

The cubit had an extremely long life and was used in some countries as late as the l960s before being replaced by metric measures. While it may be funny to think that distance units were used based on human anatomy we should not forget that the foot is still used in the United States.

Between 1868 and 1883 Potagos Panagiotis, a Greek explorer, visited Afghanistan. He reported that there was still the Stadion unit used since it was introduced by Alexander the Great.

In the Hellenistic era, different methods were used to measure distances described by Heron of Alexandria.

Measures of Length and Distance

For short lengths, ancient Greeks used body parts to measure length. The Greek finger (daktylos) was the first unit, approximating the length of an actual finger, 19.25 mm. Romans later on measured a Roman finger at 18.50 mm, while an Egyptian finger was 18.75 mm.

Then it was the palm (palaiste). One Greek palm was 77 mm, a Roman palm was 74 mm and an Egyptian palm was 75 mm, all approximately four daktyloi (four fingers.)

Other parts of the human body were the orthodoron (a straight hand’s width or 11 daktyloi); pous (foot) at 308 mm or 12.13 inches; pygme (18 daktyloi).

The Rivergod Nilus with 16 babies as described by Pliny the Elder represents the 16 cubits to which the Nile river in Egypt rose annually.

In Ancient Greece, Schoinion, a word meaning rope, was a unit of a standard length to measure the length of land, hence Schoinourgos, the land surveyor. It was a learned method as there are references that Heron of Alexandria knew, for example, that the length of the schoinion could change by humidity and he gave some recipes on how to keep the distance as constant as possible, by hanging weights or smearing the schoinion with wax. The schoinion was 100 cubits divided into eight hammata (knots).

A halysis (metallic chain) could be used. This did not have the problems of the cord but it was probably expensive and too heavy to be used as often as the schoinion. A kalamos was a measuring rod from reed or wood. For area measurements ancient Greeks used the aroura: it literally meant arable land and was used to describe a squared square.

Weights and Coins in Ancient Greece

Ancient Greeks measured volume according to either dry or liquid capacity, suited respectively to measuring grain and wine. A common unit in both measures throughout historic Greece was the cotyle or cotyla the absolute value of which varied from one place to another between 210 ml and 330 ml. The basic unit for both solid and liquid measures was the κύαθος (kyathos, plural: kyathoi).

In ancient Greece, a talent (talanton in Greek) was a standard unit of weight used to balance a two-armed scale when weighing objects. Talanton comes from the verb ταλαντεύομαι, meaning oscillate, describing the operation of the two-armed scale.

In pre-classical times, the talent was often used for weighing gold and silver but also mentioned in connection with other metals, ivory, and frankincense. In Homer’s epics, it is always used to weigh gold and is thought to have been quite a small weight of about 8.5 grams (0.30 oz).

The later Attic talent was of a different weight than the Homeric but represented the same value in copper as the Homeric did in gold.

In later times, the Greek talent was also called Attic talent (from Attica) and was used to measure heavier weights, specifically 26 kg (57.3 lbs).

The Greek talent was also a currency: a Greek talent of silver was 6,000 Greek drachmas, or 36,000 Greek obols.

For measuring liquids, ancient Greeks used the amphora quadrantal to measure volume. It was approximately the same as today’s cubic foot, around 26 liters. A full Dressel amphora of the 1st century BC weighed around 50 kg used for olive oil, wine, and fish brine. One Greek metretes was around 39 liters (1.5 amphorae).

For dry bulk like grain, the Greeks in Egypt used a larger unit of 52 liters (2 amphorae) called Ptolemaic medimnos weighing 40 kg when filled with wheat (dry wheat weighs 780 kg/m3). It should be noted that Naucratis, the first Greek colony in Egypt, was an important trade hub in the Mediterranean.