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Weighs and measures display 1

Exhibition number: Displays 37

Shop weights and measures have been checked by government for centuries. These are some of the Cardiganshire measures.


Weights and Measures

Apothecaries (Chemist’s) Weights

It is almost impossible to buy and sell without weights and measures, and these must be accurate. For centuries the government has controlled and checked weights and measures.

Over the years, and in different countries, measurements were defined by various laws, but it was not until the last century that they became really standardised.

The standards were often divided into twelfths and sixteenths (unlike the decimal system which is divided into tenths).

The standard weights, volumes and lengths displayed here were used by Cardiganshire County Council until 1974 to check shop and other weights and measures. They are stamped to show that they have been checked every now and then by central government and found to be accurate.

The stamps usually include the number 570 representing Cardiganshire as well as a crown and the initials of the reigning monarch.

Weights and measures used in shops, bakeries, offices, farms and the home are also displayed.

Weighing Equipment

There were 3 main methods of measuring the weight of goods.

1 Balance Scales - where scales were either hung from a beam or rested on a balanced beam. These were the most accurate since the scales could be seen to balance before use and the weights were easily checked.

2 Steelyard - where a weight was slid along one end of a hanging beam while the object to be weighed was at the other. The beam acted as a lever so heavy objects could be weighed with small weights. It was essential for the divisions along the beam to be accurately marked.

3 Spring Balance - where the objects being weighed stretched a spring on to which a dial was fixed. There are more convenient than scales but not so accurate.

Most of the measuring devices on display are balances and were used with a combination of disc or bell weights.


Most old weights are based on the pound which comes from the Roman libra (hence lb) and uncia (ounce - then one twelfth of a pound). It was used all over Europe from Mediaeval times, but each country had a different standard.

Most things were measured in Avoirdupois weights (grains, ounces, pounds, stones, quarters and hundredweights)

Precious metals, and jewels were measured in Troy weights (grains, pennyweights, 'ounces' and 'pounds')

Chemicals were measured in Troy 'ounces' and 'pounds' but had different subdivisions. They went out of use by 1900.

Measuring Length

Most old measurements are based on the yard
(3 feet = 0.9144 metres).
Standard lengths were used when selling materials, particularly cloth, and when measuring land.
Craftspeople used to use their own standard measuring sticks for example when cutting slates to size.

Parts of the adult human body were used to measure things
adult's thumb's width = 1 inch
Foot = 12 inches
Hand = 4 inches (used to measure horses)
Yard = a stride; two yards = outstretched arms 

Measuring Volume

Liquids and some produce such as seed, grain, salt, sand and coal was sold by volume based around the gallon
(8 pints = 4.546 litres = 277.274 cubic inches).
Smaller volumes were measured in fluid ounces and drams 



Next in the Virtual tour of the Museum COINS DISPLAY